
Windows Defender Service Troubleshooting Checklist
If Windows Defender won't start, won't update, or shows error messages like "Service stopped" or ...
Software troubleshooting desk

If Windows Defender won't start, won't update, or shows error messages like "Service stopped" or ...

You try to enable BitLocker or see a drive status showing 'invalid configuration.' This usually m...

If you see a BitLocker proxy error while setting up encryption, the setup process usually stops w...

If you see error 504 when trying to activate Windows while connected to a VPN, it usually means t...

If you see 'Connection refused' or 'Service not running' when opening Windows Security, the under...

If you see Error 429: Too Many Requests while using Command Prompt (cmd.exe) to call...