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0x000000EFWindows BSOD codes

CRITICAL_PROCESS_DIED (0x000000EF) — Windows blue screen

A process required to run Windows terminated, so the system stopped to protect itself.

Severity: highWindows 10Windows 11

Technical meaning

A core system process that Windows cannot run without has exited or crashed, so the kernel halts the machine with stop code 0x000000EF instead of continuing with a broken state.

Symptoms

  • Blue screen with the stop code CRITICAL_PROCESS_DIED after the Windows logo.
  • The PC restarts into recovery or loops between the logo and the blue screen.
  • Recently installed drivers, updates or a new disk appear just before the crashes begin.

Most likely causes

  1. 1Corrupted system files or a half-applied Windows update that broke a core component.
  2. 2A faulty storage device or file-system damage on the Windows partition.
  3. 3An incompatible driver or unstable memory/overclock that kills a protected process.

How to fix it

  1. 1Boot into Windows Recovery: interrupt power three times, or boot from installation media and choose “Repair your computer”.
  2. 2Open Command Prompt and run “chkdsk C: /f /r” to repair file-system and sector errors.
  3. 3Run “sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows” to restore protected system files.
  4. 4If SFC finds damage it cannot fix, follow with “DISM /Image:C:\ /Cleanup-Image /RestoreHealth”.
  5. 5Remove the most recent update or driver from recovery, then boot normally and reinstall the vendor driver.
  6. 6Still failing? Back up your data and use “Reset this PC — keep my files” before assuming a hardware fault.
Reset / command
# From Windows Recovery (WinRE) Command Prompt
chkdsk C: /f /r
sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows
DISM /Image:C:\ /Cleanup-Image /RestoreHealth
bootrec /fixmbr && bootrec /fixboot && bootrec /rebuildbcd
dism /online /cleanup-image /restorehealth

Frequently asked questions

Will I lose my files?
chkdsk, SFC and DISM only repair system files; your documents stay. Only “Reset this PC” or a clean install removes apps and data.
Can bad RAM cause it?
Yes — unstable memory or an aggressive overclock can kill a protected process; test with Windows Memory Diagnostic if the disk is healthy.

Copies: 17,460 · Views: 41,920 · Updated: Sep 18, 2026

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