Few things are more frustrating than working with a slow computer. Whether your computer just started crawling or you've put up with poor performance for months, fixing the issue is important so you can get back to work.

Let's look at various scenarios that could be dragging your system to a halt. You could be suffering from one or several of these causes. By going through each of these, you can pinpoint where your issue lies.

You Need to Reboot

Sometimes, a slowdown comes from a temporary Windows issue. Whether it's a program using too many resources or a Windows configuration error, poor performance does come out of nowhere at times. This is especially true if you leave your computer turned on all the time. You should reboot regularly to avoid these issues.

Restarting your computer fixes all sorts of problems, so it's a wise first step when slowness pops up out of nowhere. If you reboot and the problem persists, continue with troubleshooting.

You Have Too Many Programs Running at Startup

With so much awesome Windows software out there, it's natural to want to try a lot of programs. However, you might run into a problem if too many programs run as soon as you boot your computer. Lots of software does this by default, so you might be running half a dozen apps that you aren't even using at the moment.

Thankfully, it's easy to remove startup items. If you're not sure what you should disable, check out our top startup programs you don't need. You can remove non-essential apps like iTunes, Adobe Reader, and Skype, but make sure to keep your antivirus and backup software running.

You're Infected With Malware

Just like having too many programs running could slow down your computer, having one or more malicious programs running can cause big problems, too. Even if you have malware installed that isn't spawning pop-up ads or getting in your way, it's still wasting resources.

With a few tools and a bit of time, you can beat any piece of malware out there. Review the ten steps to take when you're hit with malware, and follow the malware removal guide. Then, make sure you have essential Windows security software installed after you've confirmed that everything is clear.

You're Using Heavy Software

Some software leaves a hefty footprint on your system's performance, when a lighter alternative could get the job done just as well. Two of the most common examples are Norton Antivirus and Google Chrome.

You can completely remove Norton and replace it with a superior free security suite. To stay light, using a cloud antivirus like Panda will free up resources on your machine. Google Chrome uses a lot of RAM, which the Chrome team will fix soon. If you're not trapped in Chrome, try using Opera or a super-fast alternative, like Nitro, to keep things light.

It's also a good idea to turn Flash off in your main browser. The Flash plugin is on its way out, but plenty of sites still use it. Thus, you should still keep an extra browser around for occasional Flash needs, but disable it in your everyday browser for better performance.

Your Computer Favors Visuals Over Performance

Did you know that you can turn off all the fancy effects of Windows? By default, Windows enables colored title bars, real-time dragging, and more. However, these eye-candy enhancements take up system resources. If you don't mind a slightly less pretty experience, try adjusting Windows for best performance.

To do this, type Performance into the Start Menu and click Adjust the appearance and performance of Windows. Here, you can disable individual visual effects like maximizing animations and window shadows. If you choose Adjust for best performance, you can disable all of these in one go. In Windows 7, this will result in your computer looking like Windows 95, but see if you can get used to it.

Your Hard Drive Is Almost Full

While deleting all kinds of files won't speed up your system, a hard drive that's nearly full can affect performance. Hard drives need a certain amount of free space to function, and constantly working with a maxed-out disk might be giving you problems.

Thankfully, it's easy to clean up files and give the system some breathing room. Follow our step-by-step guide to cleaning Windows to reclaim plenty of space.

You Need to Upgrade Your Hardware

If you've run through the fixes for all the above scenarios and still aren't happy with your computer's speed, you probably have inadequate hardware. Hopefully, you're not still running Windows XP; if you are, you need to buy a new computer with a modern operating system.

For machines that are only a couple of years old, spending about a hundred dollars on upgrades can go a long way. To save money, you should prioritize upgrading the components that improve performance the most. For most machines, this means replacing the hard drive with a solid state drive (SSD) and installing more RAM.

These two upgrades will greatly boost your machine's performance and could help provide a few more years of service.

While you're replacing the components, make sure to give your PC a physical cleaning, as dust and other grime can adversely affect it, too.

Your Network Is to Blame

If you're running into issues only when browsing the web, your problem might be with your internet connection, not your machine. You'll know this is the case if your system boots up quickly and has no problem running multiple programs at once, but struggles to load a webpage.

You can perform some troubleshooting to get to the bottom of network issues. Have a look at fixing Wi-Fi slowness, items that could be slowing down your home network, and how to fix unstable Wi-Fi connections. If you've exhausted all of those options, you might need to upgrade the speed you receive from your ISP.

You Need to Run Some Scans

Before you take the nuclear step, there are a few scans to try that might fix some issues. You can run these in Windows from a command prompt. Type cmd into the Start Menu, then right-click its entry and choose Run As Administrator to open an elevated command line.

The first scan will check Windows for errors. This scan is usually performed to fix corruption errors, but it's worth a shot to improve performance, too. The command to run is:

        sfc /scannow
    

A second scan will check your hard drive for errors. If it finds any, the scan attempts to correct them. Those disk issues could be affecting performance, so this is a good one to try, as well.

To run a disk check that attempts to fix bad sectors, type the following command:

        ckhdsk /r /f
    

The system can't check the disk when you're using it, so reply Y to the prompt to run a scan at the next boot. Restart your system when you're ready, and the scan will run. This could take a while, so it's best to initialize it when you won't need your PC for a while.

You Need to Reinstall Windows

If you've tried all the above fixes and still have a speed problem, it might be in your best interest to reinstall Windows. Over time, Windows builds up crud and is prone to running into strange issues that are best fixed by a reimage.

You don't need to regularly reinstall Windows like some people say, but if you're still having an issue, it's faster to just reimage than to waste time trying to pinpoint the problem. Note that you shouldn't reinstall Windows until you've upgraded the appropriate hardware -- that would be like putting new tires on a worn-out car. Additionally, it takes time to set up Windows just how you had it, so be certain that you can't isolate the cause before taking this step.

Windows 10 allows you to refresh and reinstall using several methods. Thus, you can get a clean start without losing your data, or start over from scratch, depending on how severe your issue is. If nothing else could fix your problem, new hardware and a clean copy of Windows should do the trick nicely.

How Else Can You Speed Up?

These are ten common causes for a Windows computer running slowly, but you can probably think of others. While software fixes are usually pretty simple, nothing beats a hardware upgrade. Once you've narrowed down the problem, consider spending some money on new components to keep your system running sharply. You'll waste a lot of time waiting for the computer to catch up to you otherwise.

Once you've got a speedy system again, make sure you put simple habits into practice to prevent slowdown in the future.

What are the first things you check when troubleshooting a slow computer? Let us know your best fixes down in the comments!

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