How to Run CHKDSK in Windows 11

CHKDSK (Check Disk) is a built-in Windows utility that scans your drives for file system errors and bad sectors, and attempts to repair them. Running it can fix issues like corrupted files, slow performance, or unexpected crashes. Before you start, close all open programs and save your work, as CHKDSK may require a restart to complete the scan.

What You’ll Need

A Windows 11 PC with administrative privileges (you must be logged in as an administrator).
Enough free time: a full scan can take from a few minutes to several hours, depending on drive size and errors.
If you’re scanning your system drive (usually C:), you’ll need to restart your computer and allow CHKDSK to run before Windows boots.

Step-by-Step

Open Command Prompt or Windows Terminal as Administrator. Right-click the Start button (or press Win + X) and select “Terminal (Admin)” or “Command Prompt (Admin)”. If prompted by User Account Control, click “Yes”.
Identify the drive you want to check. In File Explorer, note the drive letter (e.g., C:, D:, E:). CHKDSK works on a specific drive letter.
Run a basic scan. Type chkdsk X: (replace X with your drive letter) and press Enter. This scans the drive and reports errors but does not fix them.
Run a scan with repairs. To fix errors, type chkdsk X: /f and press Enter. This attempts to repair file system errors.
Scan for bad sectors. To also detect and recover bad sectors, use chkdsk X: /r. This includes the functionality of /f and is the most thorough scan.
Combine options for a full check. You can use chkdsk X: /f /r to do both. For a faster scan, you can add /scan (online scan) but it won’t fix everything.
If scanning the system drive (C:), you’ll see a message: “Chkdsk cannot run because the volume is in use by another process. Would you like to schedule this volume to be checked the next time the system restarts? (Y/N)”. Type Y and press Enter.
Restart your computer. If you scheduled a scan, Windows will run CHKDSK before booting. Let it complete; do not interrupt it.
Review the results. After the scan, CHKDSK will display a summary of what it found and fixed. You can close the window.

Common Mistakes

Not running as administrator: CHKDSK requires elevated privileges. If you don’t open the terminal as admin, you’ll get an “Access denied” error.
Using the wrong drive letter: Double-check the drive letter. Running CHKDSK on the wrong drive wastes time and could cause unnecessary restarts.
Interrupting the scan: Let CHKDSK finish. Interrupting it (by pressing Ctrl+C or turning off the PC) can cause more damage.
Forgetting to schedule a scan on the system drive: If you don’t type Y when prompted, the scan won’t run at startup.
Using /f when you meant /r: /f only fixes file system errors, not bad sectors. If you suspect physical drive issues, use /r.

Tips

Use /scan for a quick online scan: Windows 11 supports chkdsk /scan which runs in the background without restarting, but it doesn’t fix everything.
Combine /f /r for a thorough check: This is the most comprehensive scan and is recommended if you’re experiencing disk issues.
Check the event log for details: After the scan, open Event Viewer > Windows Logs > Application and look for Wininit events to see detailed results.
Back up your data first: CHKDSK can sometimes cause data loss if it finds severe corruption. Always back up important files before running it.
Run CHKDSK regularly: Even if your PC seems fine, running CHKDSK every few months can prevent small issues from becoming big ones.

Troubleshooting

“Access denied” error: You’re not running as administrator. Close the terminal and reopen it with admin rights.
“The type of the file system is NTFS” but then nothing happens: This can happen if the drive is in use. Try closing all programs or running the scan from Safe Mode.
CHKDSK gets stuck at a certain percentage: Be patient; it can hang for a while on bad sectors. If it’s stuck for hours, you may need to force restart, but that’s a last resort.
CHKDSK finds errors but can’t fix them: This may indicate a failing drive. Back up your data and consider replacing the drive.
Windows won’t boot after scheduling CHKDSK: If CHKDSK runs into a critical error, it may get stuck. You can try booting into Safe Mode and running chkdsk /f from there.

Frequently Asked Questions

Can I use CHKDSK on an external drive?

Yes, you can run CHKDSK on any drive, including USB drives and external HDDs. Just specify the correct drive letter.

How long does CHKDSK take?

It varies. A quick scan can take minutes, but a full /r scan on a large drive can take hours. It depends on the drive size and the number of errors.

Will CHKDSK delete my files?

CHKDSK does not delete files, but it may move corrupted data to a folder called found.000 on the drive. In severe cases, it might mark bad sectors, making files unreadable.

What’s the difference between /f and /r?

/f fixes file system errors. /r does that plus scans for bad sectors and attempts recovery. /r is more thorough but takes longer.

Can I stop CHKDSK once it starts?

It’s not recommended. If you must stop it, you can press Ctrl+C in the command prompt, but if it’s running at boot, you can press a key to skip it (usually within 10 seconds).

Does CHKDSK work on SSDs?

Yes, but it’s less critical. SSDs handle errors differently, and CHKDSK won’t fix physical issues. Use it for file system errors, but for SSD health, use the manufacturer’s tool or check SMART status.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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