WhyCrashed

STOP 0x00000109

CRITICAL_STRUCTURE_CORRUPTION

PatchGuard — Windows' kernel integrity guard — found critical kernel data modified. Either a driver patched the kernel (old security tools, cheats, cracks do this), or memory is corrupting.

Likely causes, most common first

How to fix it

1. Remove kernel-patching software and test RAM easy

  1. Uninstall cheats, cracks, ancient antivirus versions and dubious 'optimizer' tools.
  2. Run Windows Memory Diagnostic.
  3. Update all drivers you can.

The four parameters on the blue screen

Windows shows four hex numbers with this stop code. Here's what each means — our analyzer decodes them automatically from your dump file.

Parameter 1Reserved
Parameter 2Reserved
Parameter 3Reserved
Parameter 4Type of the corrupted region

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