STATUS_SYSTEM_PROCESS_TERMINATED (0xC000021A)

What is 0xC000021A?

Error 0xC000021A occurs when a critical user-mode subsystem process (Winlogon.exe or CSRSS.exe) terminates unexpectedly. Windows immediately issues a BSOD because these processes cannot safely terminate. This is often seen during Windows upgrades, after corrupt Windows updates, or when system files are replaced by malware.

Common Causes

• Corrupt Winlogon.exe or CSRSS.exe
• Failed Windows feature update
• Malware modifying system processes

Step-by-Step Fix Guide

• 1
  Boot from Windows installation media and run Startup Repair

  Startup Repair from a Windows installation USB is the most reliable fix for 0xC000021A caused by failed updates.

• 2
  Run DISM /RestoreHealth from WinPE

  DISM and SFC can repair corrupted system files that replace the legitimate Winlogon or CSRSS processes.

• 3
  System Restore to a point before the issue

Commands & Diagnostics