Don’t Believe The Hype: Registry Cleaners Don’t Make Windows Faster

Tina Sieber 18-09-2012

do registry cleaners workMuch advice has been given on how to keep your computer running smoothly, as well as how to fix it when it has become slow. We have even published a Windows on Speed guide, written by yours truly. One thing that hardly ever makes Windows faster, however, is cleaning the registry.


The often repeated tale, that registry cleaners can improve a computer’s performance, is a myth. The unfortunate truth is that registry cleaning can cause serious issues. The potential damange can range from money wasted on a registry cleaner, time wasted on cleaning the registry, an issue caused by ‘cleaning’ registry files that were actually important, and in the very worst case to a corrupted registry and a computer that will take forever to boot. None of this is worth a theoretical and in the best of cases minimal performance increase.

In a similar article Using Registry Cleaner: Does Is It Really Make a Difference? Advertisements for registry cleaners are all over the Web. There’s an entire industry out there bent on convincing inexperienced computer users that their registry needs fixing, and that, for ten easy payments of $29.95, their... Read More , Chris has elaborated on what the registry is and what registry cleaners do. He has done an excellent job at showing you why registry cleaners by design cannot hold up to what they promise.

I am going to look at the hype around registry cleaners from a slightly different angle. What is it that actually does slow down a Windows computer and how does the registry play into this, if at all?

do registry cleaners work

Let’s look at three of the key causes for a slow computer that could theoretically be improved by cleaning or otherwise optimizing the registry.


1. Disk Fragmentation

When your hard drive fills up with data, and when files are edited and deleted, disk fragmentation cannot be avoided. While the NTFS file system does give priority to storing data contiguously, i.e. in one single piece, it sometimes has to make exceptions. For example if you start editing a file that is tightly embedded within other files with no space between them, Windows has no choice but to write whatever you add to the file to another location on your hard drive, i.e. the file gets fragmented.

Fragmentation slows down your computer because Windows has to fetch all the different parts of a file from multiple locations on the hard drive and stick them back together while loading them into RAM. Only when this process is completed, you can see the respective file.

do registry cleaners really work

So does fragmentation affect the registry? Yes, but not really. Even if registry files are fragmented, reading them doesn’t cause a significant loss in performance because the registry is loaded into the RAM when Windows boots and can be accessed instantly while Windows is running.


This brings us to the next point…

2. Maxed Out RAM

By far the biggest factor in slowing down the computer is lack of free RAM. What takes up most of the precious RAM space, is running software. When all RAM space is exhausted, Windows removes inactive RAM data and writes them to virtual RAM, i.e. storage space on your hard drive.

Now when this data is needed, it is copied back to the RAM, but only after something else was removed. These operations cause a significant delay.

do registry cleaners really work


So we just established that the registry takes up RAM space. Wouldn’t it thus make sense to clean it up and keep it smaller, so it doesn’t take up so much RAM? Theoretically, yes. In practice, however, the amount of space you can save by removing a few hundred registry entries is minimal, so it won’t make a difference.

You can, however, achieve significant improvements by either upgrading your RAM (if possible) or by closing software you don’t need and preventing it from launching along with Windows.

3. Bad Registry Entries

So finally, we have reached the registry itself. Yes, bad registry entries can cause performance issues. However, under normal circumstances this should not happen. Moreover, newer versions of Windows protect the registry from fatal events, such as a crash during a database update, by keeping two levels of log files. During system boot, the registry can be repaired or reinitialized in case serious damage occurred.

General use issues, such as occasionally installing bad software, can of course not be avoided. If you want to do your registry good, remove and don’t install crapware How To Remove Unwanted Crapware From Your Brand New Windows 7 System Read More , set up a sandbox to test software What's A Sandbox, And Why Should You Be Playing in One Highly-connective programs can do a lot, but they're also an open invitation for bad hackers to strike. To prevent strikes from becoming successful, a developer would have to spot and close every single hole in... Read More before installing properly, and if you do have to uninstall, use a tool like Revo Uninstaller to properly remove program files from your computer, including the registry.


Recommended Registry Cleaner

So what if you are 100% sure that you have an issue that can be addressed by cleaning the registry? Well, at least use a trusted tool and don’t waste any money on it. A PC maintenance tool we highly recommend Optimize Your System To Run At Its Best With CCleaner Over the last two years, CCleaner has changed quite a bit in terms of version numbers...up now to version 3.10 at the time of this writing. While visually the program actually hasn't changed much (it's... Read More is CCleaner and it contains a registry cleaner. Although we endorse this tool, we do not recommend to use its registry cleaner on a regular basis. Be sure to use it with care!

do registry cleaners work

Did registry cleaners ever cause you issues or have you seen them improve your computer’s performance? We would love to hear about your experience!

Further Reading on How to Make Windows Faster

Image credits: Binary Vortex via Shutterstock, Snail on Keyboard, Snail on RAM via Shutterstock, Snail on RAM via Shutterstock

Related topics: Computer Maintenance, Defragmentation, Registry Cleaner, Windows Registry.

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  1. Techteacher
    June 4, 2017 at 4:14 am

    I've used several free system cleaner utilities. ASC, ccleaner, Malwarebytes, AVG...and some of the iobit products(free versions only). Have always loved ccleaner with no troubles(several years of good use up to now on Win7-Win10 PC's.
    My newest machine has Win10 on it and I now simply use ccleaner + OEM Win10 system cleaner tool(standard with the program) for cleaning and optimizing my computer(a nice new HP Envy). No issues so far, but I am a fussy software cleaner so rarely has my hardware let me down. My last lappy -ToshibaL650, just retired after 5yrs good use because the screen karked it..I put that down to simple wear and tear(old age!). All good so my new SSD and i7 with LOTS of RAM!!!...

    • Tina Sieber
      June 5, 2017 at 6:27 pm

      Thanks for the insights! Have you ever used CCleaner's registry cleaning feature? What's been your experience there?

  2. SkittleNutz
    December 19, 2015 at 12:26 am

    If you guys have issues with your file system being corrupt ... run "sfc /scannow" from from your CMD prompt. It will scan you system files and will repair them.

  3. Anonymous
    July 9, 2015 at 7:47 pm

    ccleaner is the worst cleaner you can ever recommend! If you have ever analysed the data which it tries to delete from registry then you would not recommend it anymore! It delete entries from installed software like microsoft office and adobe photoshop and other tools and sometimes this trashes your computer !!

  4. CappnRob
    February 17, 2015 at 6:55 am

    Cleaned my registry with CCleaner one day... and now the computer runs slower. Especially videos. :(

  5. Sattesh
    January 31, 2015 at 1:28 am

    I somewhat disagree with this. I run the registry cleaner(Ccleaner) after uninstalling any software. It removes registry entries that the program uninstaller "forgets" to remove. I don't see much difference nowadays with my newer PC, but back when I was using an ancient computer(~ year 2000), running the registry cleaner once in a while really did speed up my PC. It even fixes some errors sometimes. I remember having a weird error message pop up every time windows boots, and after scratching my head for some time, a quick registry clean fixed my problem. That being said, aggressive registry cleaning( using premium software) can be dangerous I agree. Once I had some weird missing file error keep popping up, after a program uninstall, and I ran a registry cleaner I used to use(forgot the name), and windows had to be reinstalled. That happened once. So for me, the good outweighs the bad.

  6. Zaid Mark
    February 7, 2013 at 1:59 pm

    I also use registry cleaners sometimes CC Cleaner and sometimes Registry Recycler It is right that most people believe registry cleaners do not enhance the performance of computer. I think what matters here is which software you are actually using. Only reliable registry cleaning software can help you get your PC optimized.

  7. Gary
    January 25, 2013 at 10:36 pm

    I've used a few registry cleaners, including Ccleaner for the last few years off and on. Each time I have used CCleaner to clean the registry, I have suffered OS problems, errors, glitches etc and eventually had to reinstall.
    I do manual editing where I really need to now, almost entirely a simple search for software titles and publishers that I've uninstalled and apart from that I leave it well alone.
    I disagree entirely with the view that 'cleaning' the registry is valueless. I have quicker boots, fewer problems and no freezing, hanging or other issues since I started the manual cleaning.

  8. Jeremy Winters
    January 24, 2013 at 8:25 am

    The last time defrags were really needed were with XP. If you have Vista, 7, or 8 reg cleaners are only going to damage your computer over time not speed it up. I tried a few of the top ones, and what happened well, they play around with your computer, lie to you, and will eventually drop your OS and boot manager from your main HDD. Why? Because in modern times these "tools" do not have one important thing needed to properly fix it, and what is that? It is called the source code! I warn you do not buy into any of this as your OS will fix its own problems! The only thing you need is your OS's manufacture's antivirus! Say you are on vista, 7, 0r 8 right? Just install Microsoft Security Essentials, and run deep scans! Your OS has tools that will fix itself, and if you are required to do manual things a dev will be happy to help you...just contact them...seriously, do you want a 3rd party company you've never heard of touching files that your computer needs to run? I wouldn't....your OS since 2006ish has been able to optimize itself, and the reason most likely you have speed issues aren't due to what those things claim! For example it is most likely short memory on the HDD due to over storing, so uninstall some things, or buy an external HD, get as much ram as possible, replace, the CPU I wouldn't really overclock it, replace the HD with a larger faster 7200 RPM one, or scan with your antivirus I suggest once again Microsoft Security Essentials. If you are running too much at once then you're slowing down as you are using way too much VM. Another thing if you are complaining about your net speed clean up your cookies, your history, don't overly tab browse, um check your up and download speeds, and upgrade your net, update your router and/or modem's firmware...all of this will give you a speed boost.

  9. Paul Hays
    January 17, 2013 at 5:12 pm

    Just a couple of notes on "memory full" - Win7 is a notorious memhog. That said, there is no purpose for lots of RAM unless it's in use. Full(er) memory is to be expected, based on newer memory management schema. Balance... Great article. Thank you for it and keep writing!

  10. Luis Garza
    October 9, 2012 at 7:34 pm

    Thanks. That answers the myth. Worth noting.

  11. Nathaniel Fleur
    October 1, 2012 at 4:47 am

    The best way to clean up registry is to use software that is designed for that purpose. Most people say that registry cleaners will not do good on any PC but I say, it's the users responsibility to be mindful on which registry cleaner to download. Based on my experience, I used Regcure: together with Tune Up Utilities and it did a great job in optimizing my PC. Registry cleaners are good for cleaning up PC once in a while.. ;)

  12. Deekshith Allamaneni
    September 25, 2012 at 2:31 am

    Oh, I am saved. I use Linux most of the times. Its good as it does'ne need to have either defragmented nor get its registry cleaned(it has no global registry).

    So this is why my Windows machine gets slower if I use it as it is for over 6 months without maintenence where as my Linux box remains as fresh as a new born.

    The major problem with Windows I've found is not exactly with Windows but it is the rogue apps that peolple are bound to install. Whereas most Linux users install from their software repositories which are tested.

    Summary is, It is easy to maintain a Linux system compared to Windows.

  13. jack of the willows
    September 24, 2012 at 4:27 pm

    Interesting but where are you sources and why do u not show them on this artical to prove your arguement

    • Tina
      September 26, 2012 at 3:53 am

      MakeUseOf is not a science journal and this is not a scientific article, hence no sources. Besides, the facts, such as how does fragmentation work or how does the registry work, are facts and common tech knowledge, not scientific theses or theories, and thus don't require a source in the first place. Finally, my conclusions are mostly based on my personal experience using registry cleaners in Windows, so the source is me. As I said, this is not research or a scientific article, it's a technology article.

  14. salim benhouhou
    September 24, 2012 at 1:06 pm

    i used to believe that registry cleaners speed up my PC until i read a similar article to this

  15. bben
    September 23, 2012 at 12:16 pm

    While a registry cleaner may not speed up your computer it can fix other problems. I have seen a program that installs a few registry entries and then when uninstalled - or the program is moved, those entries are not removed on uninstall or changed on moving. This causes the program to crash when you try to reinstall, or use it after moving it.

    The ONLY ways to fix that is to either use regedit to hunt down the entries and delete them, (not a solution for the non geek) or to uninstall, remove all evidence of that program from the computer (either delete or rename all folders associated with the program.) Then REBOOT (very important) before running the registry cleaner. Then you can reinstall and it will work.

    Yes, I'm talking about you BethSoft - this has been an on going problem for over ten years with Bethesda Software and they have not bothered to fix it or to even admit that it is a problem.

    I personally prefer Ccleaner, but any decent cleaner will work. Ccleaner has many other things included besides a good registry cleaner. While I don't recommend regular use of the registry cleaning part, it is good for selectively removing cookies while allowing you to define which cookies should be left intact.

  16. Omstavan Samant
    September 23, 2012 at 8:32 am

    can you suggest browsers and other essential softwares like media players which can work by using the least possible amount of RAM with reasonable performance and features?

    • Deekshith Allamaneni
      September 25, 2012 at 2:37 am

      Light Weight Apps?
      PDF Reader: Sumatra PDF
      Browser: K-Melon, Midori.
      Media Players: M-Player.

        October 5, 2012 at 3:35 am

        how did you reach the conclusion that they are light weight?? and are the browsers secure enough for everyday use???

      October 5, 2012 at 3:34 am

      Is that article ready?? I wanted answers based on research and not based on what people feel that is why i am eagerly waiting for your article

      • Tina
        October 9, 2012 at 10:10 pm

        Sorry, the article is not ready, yet. Too many other articles on my list right now. No promises as to when it will get done!

  17. UUUnicorn
    September 22, 2012 at 1:55 am

    I use CCleaner, but only the very top button (marked "Cleaner"). I NEVER use the second one, which is marked "Registry".

    After I finish using CCleaner, I use Auslogics Disk Defrag. I set it up to "Defrag and Optimize", then I click on the box to insert a check mark for shutting the computer off when "Defrag and Optimize" is completed.

  18. raj gopal
    September 21, 2012 at 6:08 pm

    very good article , personally use ccleaner an must say very much satisfied

  19. kscmint
    September 21, 2012 at 10:06 am

    Hi, I am a software developer and have used various registry cleaners since around 2000. I agree that using a registry cleaner, by itself, will not improve performance. The reason is due to way Windows Registry works. I also agree with Richard Steven Hack that the Windows Registry is one of the worst design decisions Microsoft made. However, I digress.

    The Windows Registry is simply a line item list of values. When a program needs one of the values in the Registry, it does a sequential search for that value starting from the top. If the Registry is very large, this can become a time consuming process. So the larger the Registry grows, the more time it takes to do a search.

    When one of those values is removed by a registry cleaner or manually, it leaves a blank line in the Registry. So when a registry cleaner is run and removes the value, the Registry ends up with blank lines. There is less garbage but there are more blank lines. The net result is that to find a key, there are just as many lines to search thru to find a key. I.E., no performance improvement.

    The real performance improvement comes when the Registry is defragmented after cleaning and then compacted with a tool like Auslogics Registry Defrager. However, this is dependent on the number of Registry entries that have been removed. If a lot of Registry entries have been removed, you should see slight improvement.

    When I first started doing the clean/defrag of the Registry, I saw significant improvements I the systems I initially performed the clean/defrag on. Because I have done that on a regular basis, I do not see that significant of an improvement, if any.

    I suspect with the newer versions of Windows, registry handling may be better, although I have not researched or tested it to find out.

    If you are one to install/uninstall a lot of programs or if you have gone a very long time not doing a clean/defrag of the Registry, you may see some improvement.

  20. Eli
    September 21, 2012 at 9:50 am

    My comment has a few parts. 1. The use of registry cleaners is mainly to fix a problem not to increase speed. 2. With regard to RAM it is not easy to work in the dark. One can install the free cleanmem (available at MajorGeeks. rating of 4.88 !! ). One can see if there a RAm problem and /or if the use of Cleanmem improves. 3. Defrag does help in speed issues - go to Gizmo for recommendations of free defragmenters. 4. I tried Ccleaner, Glary Pro and Advanced system care pro in cases of unexpected problems. Glary and ASC can also optimize system performance in some aspects.
    5. The real issue is that problems usually don't just appear . Performance problems start small and then become more and more severe so it is diffficult to pin down the culprit.
    6. Revo works very well but sometimes fails to detect an installed program. In such a case one can try iobit uninstaller, myunisnstaller, or the one in Ccleaner

  21. Kevin
    September 21, 2012 at 7:31 am

    I almost completely disagree with this article. Whenever a client complains about a slow computer, one of the first things I look at is cleaning the registry. In one - admittedly extreme - case, a particular print job that used to take 40 minutes was reduced to 2 minutes simply by cleaning the registry. I do regularly see substantial performance improvements from cleaning the registry.

    I think it's important to understand what registry cleaning actually does. The registry contains (among other things) hundreds or thousands of references to DLLs. Many of them are part of Windows itself, but many others of them are part of programs that you install.

    Now when you uninstall software that isn't needed, or when you upgrade to a newer version, or for many other reasons, some of these DLLs get removed or replaced - but very often, the references to them in the registry don't get updated. That's in part due to dependencies (an uninstaller can't always assume that it's safe to remove certain things that may be used by other software), and in part due to poor quality. Many companies spend a lot of time polishing the installer for their software, but the uninstaller is often an afterthought and not sufficiently tested.

    What happens is that Windows tries to access these DLLs through the registry, and then produces an error when the DLL file that matches the registry no longer exists. Multiply that by hundreds (usually, CCleaner finds about 300+ entries when I do this), and it causes a substantial slowdown.

    A good registry cleaner will cure most of these things. I agree on recommending CCleaner; I've only ever had one problem where it corrupted an application.

    The one thing that I find overhyped is disk defragmentation. In the era of 300 GB+ hard disks, it is rare for disks to ever get fragmented enough to cause a problem. The only time I have seen significant fragmentation is if the disk is almost full (and in that case, defragmentation does improve performance). By the way, it is also worth mentioning to never, ever try to defragment an SSD - it actually damages the SSD, and there never is any benefit to defragmenting.

    Agreed on the RAM. That's the one almost universal cure I prescribe even if there is no immediate problem. Even there I have to caution. I've seen systems with 1 GB of RAM be slow even though only 600 MB were being used. In that case, the cause may well be something different. A RAM upgrade is still a cheap precaution to prevent problems in the future.

    I don't generally recommend running registry cleaners or defragmentation preemptively; only run them when there actually is a problem.

  22. Michael Avila
    September 21, 2012 at 6:11 am

    i use ccleaner pro and i have a pretty old laptop and after use i do see a significant boost in my PC i also run tuneup utilities in turbo mode to shut off a lot of features i don't need which give it a little more of a boost and defrag often with auslogics disk defrag pro which i read about in an article on Makeuseof awhile back all these together improved my pc and it runs like brand new imo.

  23. Nikhil Tom
    September 21, 2012 at 3:45 am

    In some cases CCleaner Registry cleaner really helped me

  24. Jeremy Flynn
    September 20, 2012 at 8:12 pm

    While I understand that they make MINIMAL difference, that is still a difference. Who wants outdated registry entries that, in essence, should not be there, such as left over entries after removal of software for one example. If you are stating they do not speed up performance, than you are mistaken...granted it may be .0000000001% of a performance increase - that is still a performance increase! While you may not see this performance increase, it cannot be ignored. If we say a second here or there means nothing, then what is the point of systematically increasing the performance and the stability of a system? The other day I literally spent 3 hours to increase my boot speed by 3 seconds. Those 3 seconds gained will pay off in time :)

  25. KimChingLung
    September 20, 2012 at 2:37 pm

    I too use ccleaner but only for the occasional house-keeping. On the registry cleaning side, I normally only check for (unused) Fonts, Unused File Extensions, Obsolete Software so I know what I am getting rid of is really of no use to me. That’s what I like about this tool where you can choose only to clean up the part that you feel comfortable with. There is of course a backup function where you can reverse the operation on the registry.

  26. nikita
    September 20, 2012 at 1:47 pm did you desigen such google ads desigen.....please tell me

  27. Dinil Lal
    September 20, 2012 at 2:49 am

    Disk Fragmentation takes lot of time on my five year old 1.4 mhz amd sempron processor
    does having a faster processor like i7 or amd quad core will do Disk Fragmentation
    very very fast

    • Alan Wade
      September 20, 2012 at 9:43 am

      Is faster defrag better? not necessarily. You could google defraggers, there are always some that claim to do the job faster. Dont waste your SSD's life by defragging it, they dont have moving platters so a defrag will do nothing more than shorten the life of the drive. A faster processor with adequet RAM will do most tasks faster.
      I use Your Uninstaller which automatically removes un-needed reg keys and I get to set the aggression level of the registry search. I tried Revo but didnt like it at all, there is, in my opinion, no comparisson between the two un-installers, one works really well and one - well it works better than the built in un-installer.

      Very interesting topic Tina.

  28. Greg
    September 19, 2012 at 9:57 pm

    Linux is looking better isn't it?

  29. Mike
    September 19, 2012 at 6:26 pm

    I have been working on pc's since their inception and no registry cleaner makes the system faster. As far as making a backup of the registry, ever try restoring a reg from backup? If you do not have the skills, don't bother. And as far as defragging, not on SSD's (solid state drives), that just makes them reach MTBF (mean time between failure) sooner. ADD RAM, the best way to speed up a pc, clean cr_p, you can edit a few reg keys if you know how (menu delays, optimize pagefiles, startup and shutdown delays, swapfile performance, disable name a few). These will speed up (or appear to speed up) your pc. Fine tuning is as important to speed as is sufficient Ram. So, unless you are willing to waste time with reg cleaners and the possible failure that SOMETIMES accompany the process, do everything else

  30. Robert Gorman
    September 19, 2012 at 4:53 pm

    I have been using CCleaner for a few years now and would highly recommend it.
    If used correctly and you back up any Registry Issues found, you should be fine.

  31. Bernardo Delapasion
    September 19, 2012 at 3:39 pm

    it may not be as helpful as people may think it is but it is quite benificial for your computer to be cleaned once in a whlie

  32. Martin K
    September 19, 2012 at 3:26 pm

    Snails, as any gardener knows will avoid copper like the plague.
    So it's cruel to put them on memory chips etc.
    Which is of course why snails are not know for their IT skills.
    (Though I think there may be a couple of them answering emails on our IT helpdesk...)

    • Tina
      September 19, 2012 at 4:45 pm

      Thank you for the trivia, Martin!

  33. Rich Mc.
    September 19, 2012 at 3:05 pm

    Nice article. I have had to help friends fix their PC's in the past because someone convinced them to clean their registry but not what they should not clean...

  34. susendeep dutta
    September 19, 2012 at 12:03 pm

    I totally agree with you and I do use registry cleaner for making sure that any bad registry doesn't interferes with software installation.

  35. GrrGrrr
    September 19, 2012 at 8:38 am

    Not only I refrain from doing anything to my Registry, but also I warn others not to play around with the registry.

    All these tools should come with a STATUTORY WARNING.

    • Yashodhan Bhatt
      September 20, 2012 at 8:00 am

      Try the Auslogics Registry Defrag,its safe to use and optimizes your pc for best performance.Also it lets you create a restore point before making any change in the registry.....happy cleaning....

  36. Debbie Strain
    September 19, 2012 at 4:49 am

    I have used numerous registry cleaners in the past thinking it would help the performance of my computers however I usually end up with more crashes. I have also used CCleaner and have never noticed any improvement however it has never caused any issues either. I rarely use a registry cleaner it usually causes more problems than it is worth. If I want to address performance I just defrag and upgrade the RAM.

  37. bonioloff
    September 19, 2012 at 3:53 am

    Registry Cleaner is bad, but if it is free, than it is acceptable to used :D
    Just kidding, i am truly agree with this article..

  38. Sreejesh Kulaparambil
    September 19, 2012 at 3:17 am

    I use CCleaner on a regular basis and I must admit that I have never really thought if it improved my system performance until I read this article. I have always taken it for granted. Though nothing has gone wrong so far but after reading the analogy given by you in reply to Mr Yashodhan Bhatt's comment of a young smoker having no health issues, I think I need to be more careful using any registry cleaner. Thanks for such an informative write up. :)

  39. tarzan2001
    September 19, 2012 at 3:00 am

    This is a great article, Tina! I used to use various system management tools like Ashampoo WinOptimizer, Glary Utilities, and now CCleaner to keep my system running as fast as possible. I used the registry cleaning option quite a bit with WinOptimizer, and only once had something stop working after it was done. However, with Glary Utilities, CCleaner, and the next-to-latest version of WinOptimizer, I've noticed more problems occurring after using their registry tools, so now I just completely avoid them! And honestly, I haven't really noticed any difference between "cleaning" the registry and not--except for the fact that my computer isn't getting broken! :P

    I think the best thing to do after your computer slows down a lot is to reformat the computer. I used to do it every 3 months, but now I don't have as much free time as I used to, so I only do it about once a year. I understand that it's a big pain, and it's no fun backing everything up, and then reinstalling all the programs, but it really does make a huge difference. Plus, it allows you to install only the latest versions of the software you use, not to mention any new software you've begun using in place of previous programs, without having all of their old registry entry stragglers bogging down the system! ;)

  40. Jerry Berry
    September 19, 2012 at 2:34 am

    Since we're talking about CCleaner, let's talk about what WILL speed up your lappy -- Use C[rap]Cleaner / Tools / Startup to Disable your CrapWare!!

  41. Jeremy Collake
    September 19, 2012 at 12:57 am

    Your registry has hundreds of thousands of keys, thus 'cleaning' is more likely to cause problems than any appreciable performance increase. Registry cleaners have often wiped out my properly named registry keys, just because the more aggressive they are the better the user thinks they work. In truth, your registry hives are loaded into a highly optimal data structure in memory that is traversed very rapidly. As for 'invalid' registry keys pointing to incorrect locations, it takes minimal time for a lookup to fail in 99% of cases, and these cases are rare to start with. The *only* proven way to improve registry performance, and even then it is only marginal, is by rebuilding the registry hives themselves from scratch, thus eliminated wasted space inside their data structure. Defragmentation of the backing hive files is also *marginally* helpful in a *small minority* of cases.
    For more information:
    RegBench - Registry benchmark tool
    The Truth About Registry Cleaners:

  42. Siddhant Chaurasia
    September 19, 2012 at 12:37 am

    That is why I use a mac

  43. Richard Steven Hack
    September 18, 2012 at 11:54 pm

    I install CCleaner on all my clients' machines and recommend to them that they run it on a weekly or so basis.

    Of course, the primary purpose of CCleaner is to clean out temporary and "junk" files from the hard drive and that's why I tell my clients to run it. I don't tell them to run the Registry clean as a matter of course.

    But when I run CCleaner FOR my clients, I DO run the Registry Clean function.

    The problem with registry cleaners is that 1) you can't easily tell what improvements are made unless you look at every single registry change made, AND know enough about what that key did or does in the Registry to determine what the effect is.

    I doubt there are many PC experts outside of Microsoft who can do that AT ALL.

    And 2) you also can't tell if you're doing any damage for the exact same reason.

    For myself, I have never seen CCleaner do anything which could be traced as the cause of a subsequent fault of the system. But that doesn't mean it's never happened.

    Alternatively, I've never seen CCleaner do anything which could be traced to a significant improvement of the system.

    There is another important issue, however. The Windows Registry since Windows 98 has LONG been known as a major cause of issues with Windows. Mostly this is due to "corruption" - a vague and deliberately undefined word by Microsoft - in the Registry. This is DIRECTLY caused by the fact that the Registry is a Microsoft-produced proprietary key/value database which is open to modification by ANY IDIOT writing software in the industry! And it has NO user-available cleanup tools built in as is the case with most REAL database systems!

    Now I challenge anyone - PC expert or not - to PROVE to me that a Registry Cleaner either produces worse OR cleans better corruption than Windows and Windows software in general.

    But I think we have to assume that the developers of the Registry Cleaners that have been around a while such as CCleaner have at least SOME knowledge of what constitutes a "bad key" or "bad value" in the Registry. And the removal of such bad or unused keys and values HAS to have SOME value in keeping the Registry more robust than if such keys and values were NOT removed.

    Also, as the Windows Registry has been getting massively larger with every release of Windows, I think defragging the Registry also has some value, if not much compared to the amount of RAM available these days. I think the removal of unnecessary deleted space probably helps to some small but unmeasurable degree the robustness of the Registry.

    So I must disagree with the overall tone, if not the specific suggestions, of this article. I think on balance end users SHOULD use Registry Cleaners as long as they use ones which have been well reviewed and been around a long time such as CCleaner.

    Also, without actual STATISTICS, compiled by someone with detailed knowledge of many tests conducted over many Windows systems by people knowledgeable in the actual content of the Registry, I don't think one can establish anything definitive on this issue.

    • Richard Steven Hack
      September 19, 2012 at 12:00 am

      I should add, however, that the TITLE of the article is correct. You really won't see much, if any, improvement in SPEED by cleaning the Registry. That isn't the main reason TO clean the Registry.

      The main reason is to improve its robustness as much as can be done given it's total vulnerability to bad programming.

      The Windows Registry is without question THE WORST design decision Microsoft ever made.

      The main reason Linux is SO much more reliable than Windows is the fact that it has nothing in it that resembles the Registry. Most of its configuration is controlled by TEXT files which are NEVER updated once set. (There are, however, some "database" files involved in the desktops - KDE or GNOME - and they can be messed up on occasion by bad updating during operation.)

    • Jeremy Winters
      January 24, 2013 at 8:30 am

      It is the fault because it doesn't have the source code, so it is just hitting files at random. :D

  44. Lee
    September 18, 2012 at 10:26 pm

    I used to run CCleaner on my registry every once in a while, and then it caused a problem that, to a normal computer user, would make the computer completely unusable. I ran the registry cleaner and "fixed" everything it found. Then, when I rebooted, my Windows XP logon screen showed no user accounts. It was just blank. To fix it, I had to reboot into safe mode (where it unhid the Administrator account), go back into the registry, and add some key to unhide my user account by default.
    After that, I only ever use CCleaner for anything relating to my registry if there's a problem, and I don't use anything else. I've read so many of these articles explaining why registry cleaners don't work.

    Also, the article mentions using Revo Uninstaller. I used this for a while to uninstall everything (so it would get rid of the crap files/registry entries they left behind). I also have stopped using this after a bad experience.
    About a month ago I was uninstalling a program with Revo. Not paying attention, I deleted every file it found and every registry entry. After I deleted all the registry entries, the next page was detecting the Internet Explorer folder in Program Files. When I saw that, I figured that it probably just deleted all the registry entries for IE. Sure enough, it must have, because I could no longer use IE and Windows Explorer was also acting screwy. I also could not reinstall IE normally because Windows thought it was already installed, and I could not uninstall it because it wasn't in the Remove Programs list (nor in Revo).
    To re-install it, I think I was able to reboot into safe mode and run the installer.

    • Tina
      September 18, 2012 at 10:49 pm


      Your experience with Revo Uninstaller is shocking. On the other hand, I can also see humor in it. I wonder what program it was that you uninstalled that insisted on taking IE with it. Actually, that's not necessarily a bad idea. Too bad it also damaged Windows Explorer and didn't thoroughly remove IE. :)

      Anyhow, thank you for the heads-up regarding Revo Uninstaller. The take home message is, don't use such software, unless you understand what it does, enough to intervene in case it messes up.

      Same is true for almost anything you do on the PC. For example do not install software, unless you know what it is you are installing. That doesn't mean installing software is always bad, but it can turn out to be horrible if you do it blindly. Only difference to registry cleaners is that you can get a lot of benefits out of software. But as I explained above, there are little to no benefits in running a registry cleaner.

      • Lee
        September 18, 2012 at 10:57 pm

        I actually don't quite remember which program it was (I was doing a huge cleanup of my old computer when it happened). I think I might know but I'm not certain.

        Revo does work if used properly (and it would have been much less of a headache had I left System Restore turned on..). One big problem though is that many of the registry entries are just random numbers and letters so it's very hard to tell which ones may actually be connected to something else, so if you take the time to look through them, you probably wont get too far.

        • Mark
          September 20, 2012 at 5:51 pm

          i also had problem with Revo during it's uninstallation of software. my browser (IE, ff, chrome) icon doesn't show anymore. it shows something like a rectangle, white thingy instead.

  45. mikemflannery
    September 18, 2012 at 10:01 pm

    I would have to agree with Tina on this one. Although I have often used CCleaner's registry cleanup tool I have never really seen it make any noticeable difference to the speed of PC and I have used it on everything from XP onwards.
    More often than not I use a reg cleanup after ridding a PC of a piece of malware or crapware and I usually only allow it to cleanup the reg keys associated with said malware/crapware.
    Have any of you ever ran reg cleanup tool right after installing windows before doing anything else? I have tried this once or twice and it seemed strange that there could be invalid registry entries on a fresh install of windows!!
    Anyways that's my two cents :-)

  46. Boyd Yocum
    September 18, 2012 at 9:12 pm

    In my experience I run a cleaner once in a while (maybe every 3-6 months) I do however do a full backup of my registry just in case I do try out different programs and such but I do make sure that I have a before and after back up in case of an issue.

  47. Prashanth
    September 18, 2012 at 8:19 pm

    Cleaning the registry can be useful or not - depending on the Windows version and the program used to clean the registry.

    Cleaning the registry actually helps system performance if you are on a Windows XP with less than or equal to 1GB Ram. I have run the tests myself, and have seen myself the good things brought by registry cleaners (I used RegCleaner back in those WinXP days and before).

    However, if you are on Windows 7 with more than 2G of RAM, then registry cleaning, as you point out may not considerably enhance the system performance.

    Coming to the point of whether cleaning registry causes any actual problems, this is my take:
    I personally have used a lot of registry cleaners (RegCleaner was my first, and I loved it, CCleaner, Comodo, Glary and so on...)
    I think I know much about the registry - If I am careful, then I know what reg keys to keep and what to delete. However, I have been blindly selecting all the registry keys these programs showed and cleaned them in the past and I have not encountered ANY issues resulting from cleaning the registry.

    I should point out that Windows does a pretty decent job with registry since Windows 7. So I do not bother with registry anymore, but until Windows 7, I actually needed to worry about the registry.

    • Tina
      September 18, 2012 at 10:45 pm

      Thanks for the insights, Prashanth!

      You made two very good points. When you are familiar with registry keys, it's probably safe to use a registry cleaner. And newer version of Windows have made registry cleaning more and more obsolete, not only due to increasing amount of RAM.

  48. KamilKozyra
    September 18, 2012 at 6:16 pm

    What's the opinion about "Glary Utilities"?

    • elhaj
      September 18, 2012 at 6:54 pm

      the problem with most maintenance software is that they they require a certain ammount of knowledge from the user or they may (and will) cause problems othe then that "glary utitlities" is a good software, on the other hand CCleaner can be safley used by new users.

      • Tina
        September 18, 2012 at 7:43 pm

        Totally agree with elhaj's comment, couldn't have said it any better.

        We also recommend Glary Utilities, by the way. However, we do not recommend cleaning the registry.

    • Jeremy Winters
      January 24, 2013 at 8:27 am

      There is no point in using them as they don't have your OS's source code, so really they are just butchering your registry, sys32, and so on files...there is no advantage in using them really as they will blue screen ya eventually. D:

  49. Yashodhan Bhatt
    September 18, 2012 at 6:16 pm

    i am afraid your description is a half truth..i defragment registry every three days....nothing has happened so far!! my system is 14 months old...

    • Tina
      September 18, 2012 at 7:42 pm

      Your experience is in no way contradicting with what I wrote. However, your logic is a little flawed. It's like saying you have been a smoker all your life (at age 20) and don't have any health issues. Sure, nobody said you would see the consequences right away or that there are guaranteed consequences. You are just increasing the likeliness that something will go wrong. It's all statistics.

      The key question is, do you see any benefits by defragmenting the registry? You probably can't tell because you're not conducting a scientific study and that's totally fine. All I am saying is that the dangers of registry cleaning (not so much concerned about defragmenting) outweigh the theoretical benefits. Either way, your choice.

      • Deekshith Allamaneni
        September 25, 2012 at 2:33 am

        @Tina Siber
        Great answer.

  50. xbalesx
    September 18, 2012 at 5:51 pm

    Interesting write up...I use a registry clean up on a quarterly basis.

    • Tina
      September 18, 2012 at 7:37 pm

      And have you ever experienced any improvements?

      Are you familiar with registry keys and do you check what the software suggests to do or do you go with whatever it recommends?