How to run chkdsk before boot

CHKDSK is a command we used in Command Prompt to scan, check and repair hard drives in our computers. In Windows 11 or Windows 10, using chkdsk is no different than using it in any previous version of Windows. However, you will need to give the Command Prompt (CMD) administrative privilege in order for chkdsk command to work.

Run CHKDSK in Windows 11/10 from Command Prompt

If your target hard drive is not a boot drive, meaning that the drive isn’t where your Windows is located, using chkdsk in command prompt will scan and repair the target drive immediately.

1. Go to Start Menu. Type CMD.
2. From the result, right click Command Prompt, then click Run as administrator.
   
3. If “User Account Control” ask for permission, click Yes to proceed.
4. In the command prompt, type:

   chkdsk [driveletter] /f /r /x

5. For example:

   chkdsk C: /f /r /x

   

6. Chkdsk will then run to scan the selected disk for errors and repair them automatically. It may take hours if you have a huge and messy drive.

Why do we need the parameters “/f /r /x” when doing chkdsk?

Well, if you enter chkdsk, the command itself will only scan the disk and show you the disk’s status. It won’t repair anything without the parameters.

• To allow it to fix errors it finds, “/f” is needed.
• If you want it to also locate bad sectors on the drive and recover readable information, “/r” is needed.
• To force it to dismount the drive before begin checking the disk, “/x” is needed. This is recommended to make sure there is no running application in that particular drive that may interfere the chkdsk process.
• If you need more info on other parameters you can use, go to this chkdsk docs from microsoft.

Run CHKDSK in Windows 10/11 Before Boot

If you want to chkdsk your primary drive where you store and boot your Windows, usually C: drive, chkdsk will need to run before booting into Windows. It’s because chkdsk cannot be run if the drive is in used, especially if there is any system core file in the drive which Windows relies to work.

Note: If you cannot even boot into Windows, skip this method and go to the next one.

Here’s how you can set chkdsk to run before boot in Windows 11/10:

1. Follow step 1-4 in the instruction above.
2. In the command prompt, enter chkdsk commands with the parameters. For example:

   chkdsk C: /f /r /x

3. If chkdsk detects that the drive you want to scan is a boot drive, it will shows “Cannot lock current drive. Chkdsk cannot run because the volume is in used by another process“, and ask if you would like to schedule the drive to be checked the next time you reboot/restart your computer.
4. Type and enter Y.
   
5. Restart your computer.
6. Chkdsk will run automatically during your next boot before booting into Windows.

If you cannot even boot into Windows

If you are facing serious issue where you can’t even boot into Windows, you can force your PC to boot into recovery mode and open command prompt from the RE mode.

For more info about how to launch CMD on boot, read: How to Startup Repair Windows 11/10 using Command Prompt.

When do you need to run chkdsk for your drives

Gradually and as frequent as you like. Chkdsk, unlike defragmenting, it won’t do harm in any way to your drive no matter how frequent you run it. If you have not been running for a while, run it now. It’s recommended that you run chkdsk for each of your hard drive once a month.

If encounters freezes, hangs, drives or CPU running at 100% all the time in Windows, run chkdsk. There may be errors on the disk that cause all the problems.

Why is chkdsk stuck at certain percentage for a long time

Chkdsk may take some time to finish. We are talking about several hours here depending on the size of the disk and how much space it was used. Try to wait it out. We usually let our system to chkdsk overnight.

If chkdsk still stuck at certain percentage even after 10 hours of running, try to restart the run. It may indicates that your drive is starting to fail. Backup immediately and replace a new drive ASAP before it goes completely broken.

Description for sharing: A short guide on how to run CHKDSK (with parameters you can use) from Command Prompt in Windows 11/10 or before booting into Windows.

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