How to Fix 'Remote Desktop Module Missing mstscax.dll' Error - Fix Windows Security Proxy Error Not Working-Fixing Security Token Errors After Changing Windows Password

Updated 2026-06-14 09:53:25backup-recovery
How to Fix 'Remote Desktop Module Missing mstscax.dll' Error - Fix Windows Security Proxy Error Not Working-Fixing Security Token Errors After Changing Windows Password
Before changing system settings, save your work and note the exact error text so you can compare results after each step.

Extra verification checklist

  • Restart the affected app after changing permissions or configuration files.
  • Test the same workflow in a clean browser profile or a temporary user account.
  • Compare the result on another network if the error may be connection related.