CHKDSK: How to Check and Repair a Disk on Windows 11 and 10

CHKDSK is the Windows command that checks a drive’s file system for errors and, with /f or /r, repairs them. Run on its own, it only reports. Admin Command Prompt, then the command with a drive letter. The system drive gets checked at the next restart.

How to run chkdsk from Command Prompt

You need administrator rights. Without them the command refuses to fix anything.

1. Start menu. Type cmd.
2. Right-click Command Prompt, then Run as administrator.
3. Say yes to the User Account Control prompt.
4. Type the command below and press Enter.

A read-only pass on drive C first:

chkdsk C:

Errors listed? Then the repair run:

chkdsk C: /f

Windows Terminal or PowerShell as admin work the same way. The command doesn’t care which window it lives in.

One limit from the chkdsk command reference: local disks only. A network share mapped to a drive letter can’t be checked this way. We’d run it on the PC that owns the disk.

The Check button in File Explorer

No typing at all. Same engine underneath.

1. File Explorer, then This PC.
2. Right-click the Windows drive or another one. Properties.
3. Tools tab. Under Error checking, press Check.
4. Follow what the window says.

Often the answer is short: no errors found, nothing to scan. You can still press Scan drive. We’d use this route on a relative’s laptop over the phone, since nobody has to spell out switches.

Chkdsk parameters: /f, /r, /x and the rest

Most people need two letters. The rest exist for special cases and mostly apply to NTFS.

Which of the two, then. Quick logical repair with /f. Clicking sounds, slow file copies or read errors on a hard drive call for the second. Since /r already includes /f, typing both changes nothing.

After cloning a disk onto a new one, Microsoft points to /b. Rare for home users, and it takes the longest of all.

Scan first, fix later: the NTFS online scan

A gentler order on a drive you’re working on. Scan online, keep using the PC, repair the found items in one short offline step.

chkdsk C: /scan

Then, if the scan queued something:

chkdsk C: /spotfix

The spot fix only touches what the scan recorded. Less downtime than a full /f pass. On a busy work PC we’d pick this pair over a blind repair.

When chkdsk wants a restart

Run /f on C: and you get this:

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. Restart. The check runs before Windows loads, fixes errors on its own and then boots normally. A boot partition restarts the PC by itself after the check.

Leave it alone during that screen. Interrupting chkdsk isn’t recommended, although Microsoft says canceling it shouldn’t leave the volume more corrupt than before. Running it again picks up the rest.

Laptop owners: power cable in. A dead battery mid-repair is the scenario nobody wants to test.

A scan that repeats on every boot usually means the drive still has a dirty flag. We’d let one full run finish, then read the log described below before anything else.

Running chkdsk when Windows won’t start

Windows itself has a way in. After several failed starts it opens the Windows Recovery Environment on its own. From a working desktop: hold Shift and press Restart.

1. Troubleshoot.
2. Advanced options.
3. Command Prompt.

Drive letters can differ in that window. List a folder first to be sure which letter holds Windows:

dir C:\

Then the usual repair on that letter:

chkdsk C: /f

Encrypted drive? Some recovery tools want the BitLocker recovery key first, and our BitLocker guide for Windows 11 shows where it’s stored. Half-starts instead? We’d try Safe Mode: Windows 11 Safe Mode or Safe Mode in Windows 10.

No recovery screen at all? A USB stick from the Windows 11 Media Creation Tool boots into the same tools through Repair my PC.

How long it takes on an HDD and an SSD

Minutes to hours. Size, file count and the switch decide it.

Finished suspiciously fast on a big hard disk? Microsoft lists possible reasons: the volume was locked, not every sector got scanned, or the read head is failing.

On an SSD, an occasional check is fine. Repeated full-surface /r runs add write and erase cycles for no benefit, so we wouldn’t schedule them weekly.

Reading the result and the logs

The report ends with an exit code. Scripts read it, people can too.

A check at boot scrolls past before anyone reads it. The text lands in Event Viewer.

1. Press Win + R, type eventvwr.msc, OK.
2. Windows Logs, right-click Application, Filter Current Log.
3. Event sources: tick Chkdsk and Wininit. OK.

Prefer PowerShell? This prints the latest chkdsk entries:

get-winevent -FilterHashTable @{logname="Application"} | ?{$_.providername -match "chkdsk"} | fl timecreated, message

Swap chkdsk for wininit in that line to see the boot-time check.

Files named File0000.chk in the root of a FAT drive? Those are lost chains chkdsk saved after you said yes to converting them. Open them and keep anything useful.

Chkdsk, SFC and DISM: which does what

Different layers. Disk damage can break system files. Fixing the files won’t repair the disk. Our order is chkdsk first. Then DISM and SFC in the same admin window, as in Microsoft’s System File Checker article.

Updates failing? Separate story. For those we have the Windows Update troubleshooter guide.

Repair-Volume, the PowerShell version

Same job, PowerShell names. Handy in scripts.

Repair-Volume -DriveLetter C -Scan

Admin PowerShell, of course.

When the disk itself is failing

Chkdsk repairs structures and marks bad sectors. It doesn’t make a dying drive young again.

Many bad sectors on each run. New errors every week. A check that hangs at the same percent. Then we’d copy files off first and repair second. A fresh restore point in Windows 11 won’t help here, since it sits on the same disk.

New drive in? Windows goes back on with a clean Windows 11 installation or by installing Windows 11 from USB. Disk fine, Windows wrecked? We’d go the lighter way and try factory resetting Windows 11. Firmware settings during a swap: see how to enter BIOS.

Same PC, digital license? It comes back on its own, and checking the activation status takes a minute. New PC with no license? We sell a Retail Windows 11 Pro key, instant to email.

Related guides

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