How and why to run chkdsk to scan and repair a Windows 11 hard drive

Open Terminal as administrator, run chkdsk C: /scan to look for file system errors, then run chkdsk C: /f and restart to repair them.

This guide explains why chkdsk is worth running, which switch to pick for each problem, how to read the results, and what to do when the check will not run or cannot repair the drive.

How to run chkdsk on Windows 11 to scan and repair the C: drive

Chkdsk needs administrator rights, so start from an elevated window. The scan step is read-only and safe to run while you work.

1. Press the Windows key, type cmd, and press Ctrl + Shift + Enter.
2. Select Yes in the User Account Control prompt.
3. Type chkdsk C: /scan and press Enter to scan the drive online without taking it offline.
4. If the report lists problems, type chkdsk C: /f and press Enter.
5. When chkdsk says the volume is in use and asks to check it at the next restart, type Y and press Enter.
6. Restart the PC. Windows pauses before loading the desktop, repairs the drive, and then finishes starting up.

For a second drive such as D:, replace C: with its letter. A data drive is usually not in use, so the repair runs straight away instead of waiting for a restart.

What CHKDSK does and when you should run it

Chkdsk checks the file system and its metadata on a volume for logical and physical errors. Run without switches, it only reports the volume's status and fixes nothing.

It repairs the structure that tracks your files, such as the master file table, folder indexes and free-space records. It does not scan for malware or replace damaged Windows system files.

Sign you see	Why chkdsk helps	Switch to start with
Windows reports a drive needs to be scanned or repaired	The volume's dirty bit is set and NTFS wants a repair	/f
Event Viewer logs Ntfs event 55 or 98	These events say the file system is corrupt and ask for chkdsk	/f, then /r
Files or folders will not open, or show as corrupt	Damaged index or file records can make files unreadable	/scan, then /f
Reads are slow and copy jobs stall on certain files	Bad sectors can force repeated retries	/r
The PC lost power or a USB drive was pulled out mid-write	Interrupted writes can leave the file system inconsistent	/scan
Routine maintenance on an older hard drive	An occasional read-only check catches problems early	No switch or /scan

Chkdsk does not look for viruses. If files are changing or disappearing for no clear reason, run a Microsoft Defender full scan as well.

Chkdsk requirements: backups, admin rights, and drive health warnings

A repair rewrites file system records, so protect your data first. On FAT drives, a repair can change the file allocation table and sometimes loses data.

Check	Why it matters	How to do it
Back up important files	If chkdsk cannot fix the volume, a backup is the only way to recover the data	Copy your files to another drive or cloud storage before running /f or /r
Administrator access	Membership in the local Administrators group is the minimum required to run chkdsk	Open Command Prompt or Terminal with Run as administrator
Drive access	Chkdsk works only on local disks, not on a drive letter redirected over the network	Run it on the PC that physically holds the drive
Close open files	Chkdsk must lock the drive to fix errors	Close apps that use files on the drive, or let the check run at restart
Drive health warnings	A critical warning means the drive itself is wearing out, which chkdsk cannot repair	Open Settings > System > Storage > Advanced storage settings > Disks & volumes, then select Properties for the drive
Laptop power	A long /r scan on a large hard drive can take hours	Plug the laptop into mains power

The drive health page shows Estimated remaining life, Available spare and Temperature. Windows monitors only NVMe SSDs here, so SATA SSDs and hard disk drives show no health warnings in Settings.

Run CHKDSK from File Explorer in Windows 11

File Explorer offers a graphical error check in each drive's Properties dialog. It suits a quick check when you would rather not type commands.

1. Press Windows + E to open File Explorer.
2. Select This PC in the left pane.
3. Right-click the drive you want to check, for example Local Disk (C:), and select Properties.
4. Open the error-checking option in the Properties dialog and start the check.
5. Approve the administrator prompt if Windows shows one.
6. Wait for the scan to finish and read the result message.

The graphical check offers no switch choice. For a bad sector scan or to read exit codes, use the command line route below.

Run CHKDSK from Command Prompt or Windows Terminal

Command Prompt, Windows Terminal and PowerShell all run the same chkdsk.exe. The only requirement is an elevated window.

1. Select Start, type command, right-click Command Prompt and select Run as administrator. In Windows Terminal, open the same menu and choose Run as administrator instead.
2. Select Yes at the User Account Control prompt.
3. Type chkdsk D: and press Enter for a read-only status report on drive D:.
4. Type chkdsk D: /f and press Enter to fix file system errors.
5. Type chkdsk D: /r instead when you suspect bad sectors.
6. If the drive is in use, type Y to schedule the check, then restart the PC.
7. Read the summary at the end of the output before closing the window.

While chkdsk runs on a drive, you cannot open files on that drive. Interrupting it is not recommended, though Microsoft states that cancelling should not leave the volume more corrupt than before.

Run chkdsk from PowerShell with Repair-Volume

PowerShell's Repair-Volume cmdlet calls the same repair engine with readable switch names. Run it in an elevated PowerShell or Terminal window.

Your goal	Repair-Volume command	Same as chkdsk
Scan online and log problems without repairing	Repair-Volume -DriveLetter C -Scan	chkdsk C: /scan
Briefly take the volume offline and fix only logged problems	Repair-Volume -DriveLetter C -SpotFix	chkdsk C: /spotfix
Take the volume offline and fix every error found	Repair-Volume -DriveLetter D -OfflineScanAndFix	chkdsk D: /f

Chkdsk command syntax

Every chkdsk command follows one pattern: the drive letter first, then the switches. Switches can be combined, and /r already includes /f.

Part	Example	Meaning
Command	chkdsk	Runs Check Disk
Volume	C:	The drive letter followed by a colon, a mount point, or a volume name
Repair switch	/f	Fixes file system errors; the disk must be locked
Surface switch	/r	Finds bad sectors and recovers readable data; includes /f
Help	/?	Lists every switch at the command prompt

The full syntax adds about twenty switches for NTFS log size, FAT chains and speed tuning. The complete list of chkdsk commands explains each one with examples.

Understand common CHKDSK commands and repair options

Most Windows 11 users need only four commands. Pick the row that matches your problem.

Command	What it does	Takes the drive offline?	Use it when
chkdsk C: /scan	Runs an online scan of an NTFS volume and queues problems it cannot fix online	No	You want a safe first look without a restart
chkdsk C: /spotfix	Fixes only the problems logged by a previous scan	Briefly	A /scan run found errors and you want the shortest repair
chkdsk C: /f	Fixes file system errors	Yes; on C: it runs at restart	Windows reports corruption or files will not open
chkdsk C: /r	Does everything /f does and also scans for bad sectors, recovering readable data	Yes; on C: it runs at restart	You suspect physical damage on a hard drive
chkdsk D: /x	Forces the volume to dismount first, then fixes errors like /f	Yes, immediately	A data drive stays locked by an app
chkdsk D: /scan /perf	Uses more system resources so the online scan finishes faster	No	You can spare the PC while it scans

Use /x with care: it invalidates every open handle to the drive, so unsaved work in apps using that drive is lost.

Scan for file system corruption with chkdsk /scan

An online scan checks the NTFS structure while Windows keeps running. Microsoft recommends this read-only scan as the first step when looking for storage problems.

chkdsk C: /scan

Scans the C: volume online. Problems it cannot fix while the drive is mounted are queued for an offline repair with /spotfix or /f.

You should see: The summary reports whether problems were found and, if any were, which offline repair is needed next.

Scan and repair bad sectors with chkdsk /r

The /r switch reads every sector to find physical damage, then recovers what it can and marks bad clusters so Windows stops using them. On large hard drives this can take hours; on SSDs it finishes faster because there is no seek time.

chkdsk C: /r

Locates bad sectors and recovers readable information. It includes everything /f does, so you do not need to add /f. On the system drive, type Y to schedule it and restart.

You should see: After the restart, the log shows the scan stages completing and lists any bad clusters added to the bad cluster file.

Avoid running /r on an SSD over and over. Microsoft notes that repeated full-surface scans add write/erase cycles, though an occasional check is not a concern.

How to stop a scheduled chkdsk check on Windows 11

A check queued for the next restart can be removed before it starts. Microsoft does not recommend interrupting a check that is already running, but says doing so should not leave the volume more corrupt than before.

1. To see whether a check is queued, open an elevated Command Prompt, type chkntfs C: and press Enter. The output says if the drive is dirty or scheduled for a check.
2. To skip the queued check at the next startup, type chkntfs /x C: and press Enter.
3. To restore the default boot-time checking later, type chkntfs /d and press Enter.
4. Run chkdsk again when convenient, because the original errors remain until a repair finishes.

If the volume is marked dirty, excluding it only postpones the repair. The /x setting is not cumulative, so list every drive to exclude in one command, for example chkntfs /x d: e:.

How to tell if chkdsk is running and find chkdsk results

A check that runs at restart closes before the desktop appears, so its report goes to the Application log. Event Viewer shows it under two sources.

1. Press Windows + R, type eventvwr.msc and select OK.
2. Expand Windows Logs, right-click Application and select Filter Current Log.
3. Open the Event sources list and tick Chkdsk and Wininit.
4. Select OK, then open the newest entry to read the full chkdsk report.
5. Check the summary: a run that found and fixed errors says so, and a clean run says no problems were found.
6. For a check queued at restart, run chkntfs C: beforehand; the output confirms the drive is scheduled.

In PowerShell, get-winevent -FilterHashTable @{logname="Application"} | ?{$_.providername -match "chkdsk"} | fl timecreated, message prints the latest report. Swap "chkdsk" for "wininit" to see the report from a boot-time check.

Scripts can read the exit code instead: 0 means no errors, 1 means errors were found and fixed, 2 means cleanup ran or was skipped without /f, and 3 means the disk could not be checked or the errors were not fixed.

Why won't chkdsk run on Windows 11?

"Chkdsk cannot run because the volume is in use by another process"

Chkdsk needs to lock the drive to fix errors, and Windows or an app has files open on it.

1. Type Y and press Enter to schedule the check for the next restart.
2. Restart the PC and let the check finish without pressing a key.
3. For a data drive, close apps using it or run chkdsk D: /x to force a dismount.

Access denied or "You do not have enough privileges"

The window is not elevated; chkdsk requires the local Administrators group.

1. Close the window.
2. Press the Windows key, type cmd and press Ctrl + Shift + Enter.
3. Select Yes at the User Account Control prompt and run the command again.

Chkdsk will not run on a network drive

Chkdsk works only on local disks, not on drive letters redirected over the network.

1. Sign in to the PC or server that holds the drive.
2. Run chkdsk there from an elevated window.

The scheduled check never runs at restart

The drive may be excluded from boot-time checking by an earlier chkntfs /x command.

1. Run chkntfs /d from an elevated Command Prompt to restore the defaults.
2. Run chkdsk C: /f again and type Y.
3. Restart the PC.

Chkdsk finishes far too quickly on a large drive

The run was only an online scan, did not reach every sector, or the drive was locked by another process.

1. Run chkdsk C: /r and schedule it for the restart, so the scan runs offline.
2. Read the report in Event Viewer under the Wininit source after Windows starts.
3. If the hard drive still behaves unpredictably, suspect a failing read head and back up your files.

Windows will not start, so chkdsk cannot be opened

File system damage on C: can stop Windows from booting.

1. Hold Shift while you select Power > Restart to open Windows Recovery Environment.
2. Open Command Prompt from the recovery tools.
3. Run chkdsk C: /f to repair the Windows drive, then restart.

What to do if CHKDSK finds errors or cannot repair the drive

Chkdsk reports errors but says it did not fix them

The run was read-only, because /f, /r or /scan with a follow-up repair was not used.

1. Run chkdsk C: /f from an elevated window.
2. Type Y if asked to schedule the check, then restart.
3. Run chkdsk C: /scan afterwards to confirm the volume is clean.

Chkdsk cannot repair the drive or the same errors return

Failing hardware, an outdated storage driver or firmware, or bad sectors keep damaging the file system.

1. Back up everything readable on the drive right away.
2. Run chkdsk C: /r once to recover readable data from damaged sectors.
3. Update the storage controller driver and the drive firmware from the PC or drive maker.
4. Check Settings > System > Storage > Advanced storage settings > Disks & volumes > Properties for a critical warning on an NVMe SSD.
5. Replace the drive and restore from your backup if errors keep coming back.

Files went missing after chkdsk on a USB stick or FAT drive

On FAT drives, chkdsk can save recovered fragments from lost chains as files instead of their original names.

1. Open the root folder of the drive.
2. Look for files named File0000.chk, File0001.chk and so on.
3. Open them in a suitable app or rename them with the right extension to check whether they hold your data.

Chkdsk runs at every startup

The volume stays marked dirty because the repair did not complete.

1. Let one check finish completely without interrupting it.
2. Run fsutil dirty query C: in an elevated window to see whether the volume is still dirty.
3. If it stays dirty, run chkdsk C: /r and back up the drive, as the hardware may be failing.

Chkdsk on Windows 11 FAQ

How do I run chkdsk on the C: drive?

Open Command Prompt as administrator, type chkdsk C: /f and press Enter. Because Windows is using C:, chkdsk asks to schedule the check; type Y, then restart the PC. The repair runs before the desktop loads.

Should I run chkdsk /f, /r, or /scan in Windows 11?

Start with /scan, which checks the drive online without a restart. Use /f to fix file system errors it finds. Use /r only when you suspect bad sectors, because it reads every sector and takes much longer on hard drives.

Does chkdsk fix problems on an SSD, or is it only for hard drives?

Chkdsk repairs the file system on SSDs and hard drives alike. On an SSD, /r runs faster because there is no seek time, and marking clusters bad is a logical change. Avoid repeated /r runs, which add write cycles.

Can chkdsk delete files or make data loss worse?

Repairs on FAT drives change the file allocation table and sometimes lose data, and lost fragments may be saved as .chk files. Cancelling it does not add corruption, according to Microsoft. Back up important files before running /f or /r.

Why does Command Prompt run chkdsk at startup?

Windows runs chkdsk at startup when a check was scheduled with Y, or when the volume's dirty bit is set after corruption is detected. Run chkntfs C: to see whether the drive is dirty or scheduled for a check.

How do I tell if chkdsk is running?

A running check shows progress in its Command Prompt window, or as a full-screen check before Windows loads. Afterwards, Event Viewer's Application log holds the report under the Chkdsk or Wininit source.

How do I stop chkdsk while it is running?

To stop a check queued for the next startup, run chkntfs /x C: as administrator. Microsoft advises against interrupting a running check, though doing so should not add corruption. The original errors stay until a repair finishes.

How does chkdsk work?

Chkdsk reads the file system's records, such as file entries, folder indexes and free-space maps, and checks that they agree with each other. With /f it corrects mismatches, and with /r it also reads every sector to find physical damage.

How long does chkdsk take?

A /scan or /f run on an SSD often completes quickly. A /r scan on a large hard drive reads every sector, and Microsoft notes runs of several hours are not unusual. Drives with millions of files also take longer.

What should I do if chkdsk finds errors but cannot repair them?

Back up the drive straight away, then run chkdsk /r once to recover readable data. Update storage drivers and firmware. If errors keep returning, the drive is likely failing and should be replaced, then restored from backup.

Bottom line: when to run chkdsk on a Windows 11 hard drive

Run chkdsk C: /scan whenever Windows reports drive errors or files will not open, follow it with /f to repair, and keep /r for suspected bad sectors on a hard drive. The online scan is read-only and needs no restart, /f fixes the file system safely at boot, and /r is the slow full-surface pass that only physical damage justifies. Back up first, because chkdsk repairs structure, not failing hardware.