Check Your Disk for Errors
Files going missing, programs crashing on launch, or Windows nagging about disk errors all point to a struggling drive. CHKDSK is Windows' built-in disk doctor — it scans for bad sectors and file-system damage and fixes what it safely can. Run it before you assume the drive is dying.
TL;DR / Quick Fix
Quick fix: open Command Prompt as administrator, type chkdsk C: /f /r, and restart when asked — the scan runs before Windows loads. It can take 30 minutes to hours on big drives. If it finds bad sectors, back up immediately; growing bad sectors mean the drive is failing.
Follow these steps
- Open an administrator Command Prompt. Press the Windows key, type cmd, right-click Command Prompt, and choose Run as administrator. CHKDSK needs full privileges to lock and scan the drive.
- Run the full check command. Type chkdsk C: /f /r and press Enter. The /f fixes file-system errors; the /r finds bad sectors and recovers readable data. Replace C: with the troubled drive's letter if different.
- Schedule it for the next restart. Windows cannot scan the system drive while running, so it asks to schedule the check — press Y and restart. The scan runs automatically before Windows loads.
- Let it finish uninterrupted. The scan shows progress in stages and can appear stuck at one percentage for a long time — that is normal on big drives. Interrupting mid-scan risks leaving repairs half-done.
- Read the results in Event Viewer. After rebooting, open Event Viewer, Windows Logs, Application, and find the Wininit entry — it holds the full CHKDSK report: errors found, bad sectors, and what was fixed.
- Back up if bad sectors appear. A few repaired sectors on an old drive is wear; growing counts are a dying drive. Back up now, then check System File Checker with windows-sfc-scannow — disk damage often corrupts system files too.
What NOT to do
- Do not interrupt the scan because it looks frozen. Stage progress pauses for long stretches on large drives — patience prevents half-finished repairs.
- Do not run CHKDSK /r on an SSD expecting miracles. SSDs handle bad blocks internally; the scan still works but the interpretation differs — check the maker's health tool too.
- Do not keep using a drive with growing bad sectors. Each new bad sector is the drive telling you its time is short — migrate your data promptly.
- Do not confuse CHKDSK with defrag. CHKDSK repairs damage; defragmenting reorganizes files — different tools, different jobs.
Frequently asked questions
How long does CHKDSK take?
From 30 minutes on a small healthy drive to several hours on a large failing one. The /r sector scan is the slow part — plan around it.
Will CHKDSK delete my files?
It repairs file-system damage and can orphan badly damaged files, but it does not delete healthy data. Back up first anyway — a failing drive is unpredictable.
What is the difference between /f and /r?
/f fixes logical file-system errors quickly; /r does everything /f does plus a full surface scan for bad sectors. Use /r when you suspect physical drive trouble.