How to fix Error 670 on Windows 11

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Windows 11 – Error 670 (WOW Assertion Error) Troubleshooting Guide

Why This Error Happens

Error 670, manifesting as a “WOW Assertion Error,” typically occurs when the Windows-on-Windows (WOW64) subsystem encounters a mismatch while translating 32-bit application calls into the 64-bit Windows 11 environment. This is most commonly caused by corrupted system files, an incompatible or outdated 32-bit driver/DLL, or improper registry entries left behind by a faulty application update. In many cases, this is triggered by third-party software attempting to hook into system processes without proper WOW64 compatibility layers.

Step-by-Step Resolution Guide

  1. Run the System File Checker (SFC) and DISM tools to repair corrupted system files:
  • Open Command Prompt as Administrator (right-click Start → Terminal (Admin)).
  • Run: sfc /scannow
  • If issues remain, run: DISM /Online /Cleanup-Image /RestoreHealth
  • Restart your PC after completion.
  1. Check and repair the WOW64 registry hive:
  • Press Win + R, type regedit, and press Enter.
  • Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node.
  • Look for any entries with corrupted or blank values related to the application throwing the error, and back up the key before deleting any suspicious entries (right-click → Export).
  1. Update or reinstall the specific 32-bit application causing the error:
  • Uninstall the problematic app via Settings → Apps → Installed Apps.
  • Download the latest Windows 11–compatible version from the official vendor site.
  • Reinstall using “Run as Administrator.”
  1. Verify Windows Update status, since missing OS patches can cause WOW64 compatibility gaps:
  • Go to Settings → Windows Update → Check for updates.
  • Install all pending updates, including optional driver updates.
  • Restart the system.
  1. Disable third-party overlay/injection software (e.g., antivirus hooks, overlay tools like Discord/GeForce Experience) temporarily to rule out DLL injection conflicts with WOW64 processes.

Alternative or Verification Steps

  • Verify the fix: Open Event Viewer (eventvwr.msc) → Windows Logs → Application, and confirm Error 670 no longer appears after reproducing the original action that triggered it.
  • Alternative fix: If the error persists, create a new local user profile (Settings → Accounts → Other users → Add account) and test the application there — profile corruption can also trigger WOW64 assertion failures.