Exactly how long does it take Windows to load up? That question is almost as futile as, "How many licks to the center of a Tootsie Pop?" It just seems to take forever. There are several things you can do to make Windows start faster, but maybe part of the problem is that your Windows computer is performing the CHKDSK function on every startup.

Have you seen that roll up on your screen while you're waiting? Does it happen to you a lot? Ever wonder what it is, what it does, and if Windows really needs to do that? Read on, my friend, and we'll answer those questions together.

What Is CHKDSK?

CHKDSK is a command in the Windows command line to run a program, or utility, known as Check Disk. You can see where the command comes from. The Check Disk program is there to make sure that the computer's files and file system are in order (CHKDSK is different to SFC and DISM). It also checks the physical disk to see if there are any damaged sectors and tries to recover the data from them. But what does that really mean?

Running a CHKDSK Scan in Windows Command Prompt

Try thinking of your drive as being a hall full of filing cabinets. Sometimes files get put in the wrong drawers and sometimes the drawers break.

Let's say the person using the room yesterday took out a bunch of files, put some back in the wrong places, left a bunch of them lying around, and maybe was a bit rough with the drawers. That's the idea behind what happens when you shut down your computer by the power button, instead of shutting it down through your Start menu. Most people do that because their Windows takes too long to shutdown.

windows 10

Now you need to go in there and do a bunch of research. You open the door, you stand there mouth agape, and then you think to yourself, "I just can't do this today." That's pretty much what your computer does when its file system is messed up.

Imagine now, that you have a co-worker whose sole purpose is to go into the hall of cabinets, sort everything out, and fix the drawers. That person's name would be Check Disk.

Why Does CHKDSK Run at Start-Up?

Taking the hall of filing cabinets analogy a bit further, would Check Disk be able to do the job if a bunch of people were in there working? Of course not. Check Disk also wouldn't have time to do the job when the workday ends at 5 o'clock and all the power gets shut off, too.

So what Check Disk does is come in first thing in the morning, a bit before everyone else, and checks to see if everything is in order.

That's pretty much why Check Disk runs at startup on your computer. Unfortunately, Check Disk is a bit lazy and won't actually clean things up or fix them unless you explicitly tell it to do so. This is done by adding command line flags such as /f for fixing disk errors and /r for recovering info from bad sectors.

Why Does CHKDSK Run at Every Start-Up for Me?

Error message on a Windows PC

There's something wrong with your hard drive. That's the short answer.

What exactly the issue is, however, is much harder to answer. Perhaps a critical system file has been corrupted or deleted. Perhaps there are a lot of bad sectors that aren't getting dealt with. Remember, Check Disk won't fix those unless you tell it to do so. Until whatever the problem is gets fixed, Windows may try to figure out the problem by running Check Disk every start-up.

CHKDSK Seems to Run Forever. What Do I Do?

Wait. On Windows 7 and earlier, it can take hours, even days, to fully run. It's checking every single file on your computer and the larger the drive, the longer it will take. If you interrupt it, you're just preventing it from doing its job. So when you start your computer again, Check Disk will start again because it wants to finish its job.

How Do I Stop CHKDSK From Running Every Start-Up?

The answer is simple, but not necessarily easy—fix whatever is wrong with Windows. There could be just one thing wrong, or dozens. The number of possible fixes is really unknown, but let's go through the easiest and most common fixes for you to try.

1. Make Sure CHKDSK Is Not a Scheduled Task

Although unlikely, this is the easiest thing to check for.

Here is what you need to do:

  1. Type Task Scheduler in Windows search and click Open.
  2. Poke around a bit to see if there is a Check Disk task in here. If you find it, right-click on it, and select Delete. That should do it. But if this isn't the cause, read on.
    Task scheduler Windows

2. Make Sure CHKDSK Is Not Scheduled to Run

That sounds like the same thing as above, but it isn't. Check Disk could be scheduled to run just on the next start-up. To see if this is the case, here is what you need to do:

  1. Type Command Prompt in the search area of the taskbar and click on Run as administrator.
  2. In the Command Prompt window, type the command mentioned below and hit Enter. Before you continue, this article assumes that the volume label for your hard drive is C:. It could be any other letter, so check that out before proceeding.
            chkntfs c:
        
  3. If you see the following message, then Check Disk is scheduled to run on the next start.
            The type of file system is NTFS.
    Chkdsk has been scheduled manually to run on next reboot on volume C:
  4. If you get the following message, then it is not scheduled to run, and that's good. You may want to continue with the other steps below, to ensure your hard drive is good anyway.
            The type of the file system is NTFS.
    C: is not dirty.
  5. You really should let it run, but if it's causing you too much grief, you can cancel it. In the Command Prompt window, type the following command and hit Enter.
            chkntfs /x c:
        

That will prevent Check Disk from running on your next start.

How to Run CHKDSK With the Right Flags

If Check Disk is going to run anyway, you might as well tell it to fix any problems and recover what it can from the bad sectors. To do so, you will need Administrator access to the computer. Following are instructions that will work for Windows 7 and earlier versions, and then instructions for Windows 8 and more recent versions.

1. A Bit About SSDs

If you're not sure what kind of hard drive you have, check to see if your computer has a Solid State Drive (SSD) instead of a Hard Disk Drive (HDD). If your computer has an SSD, you can still use Check Disk, but it isn't necessary to run it with the /r flag. There are differences between a SSD and a HDD, most importantly that an SSD has no moving parts.

Samsung Portable SSD T5 on a desk

There is no disk to speak of, so it doesn't require that the physical drive be checked with chkdsk c: /r. But Windows still uses the same file system whether on an SSD as an HDD, so it can still benefit from the chkdsk c: /f command to repair the file system. Beyond that, Check Disk really just isn't necessary.

2. Windows 7 and Earlier

On Windows 7 and earlier versions, this could take a while. Perhaps an hour to maybe a day or more, so make sure you can spare the time. You do not want to interrupt Check Disk once it has started.

Follow these steps to proceed:

  1. Type Command Prompt in the search area of the taskbar and click on Run as administrator.
  2. In the Command Prompt window, type the command mentioned below and hit Enter.
            chkdsk C: /r
        
    chkdsk command in Command Prompt

The /r flag does try to recover information from bad sectors and assumes that you want to fix any disk errors, so you don't need the /f flag.

You'll see the command prompt tell you that it, "…cannot run because the volume is in use by another process." It will then ask you if you, "Would… like to schedule this volume to be checked the next time the system restarts? (Y/N)" Type Y and press Enter to schedule Check Disk with the repair option.

Restart your computer and leave it to do its thing. Once it's done, your file system should be repaired and Check Disk shouldn't run at start-up anymore unless there's another issue.

3. Windows 8 and Newer

Windows 8 and later take care of these kinds of issues in a much more efficient way. The file system is always checking itself for issues. Issues that don't require your hard drive to be offline are fixed immediately. Issues that require your hard drive to be offline, like when you restart, will be logged in a sort of To-Do list.

Here is what you need to do:

  1. Launch Command Prompt and execute the following command:
            chkdsk C: /scan
        
    Run chkdsk scan in Windows
  2. Once that is finished, execute the following command:
            chkdsk C: /spotfix
        
    Spotfix command in Cmd
  3. Then, type Y and press Enter to schedule Check Disk.
  4. Now, restart your computer.

This time Check Disk will run and fix any problems that were identified in the scan. Because it's only fixing those specific problems, the process only takes a few seconds to a few minutes.

Your file system should now be repaired and Check Disk should not run on start-up anymore unless there's another issue.

Getting Check Disk Checked Out on Windows

After letting Check Disk do its job, there's only one way to really check if it will run again on start-up: restart your computer. Hopefully, it won't run and you can get on with your day. If it still runs, you might have deeper problems with your file system, the hard drive, registry issues, or the operating system itself.

You should look into doing a Windows System Recovery, or possibly even a clean Windows re-install. It might also be possible that it's time to install a new hard drive. That's the extreme case, but it is a potential fix.