
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 ...

When trying to activate Windows 10, you might see an error like "We can't activate Windows on...

If you notice that Task Scheduler in Windows 11 takes a long time to open, refresh, or execute ta...

If you're having trouble with the Microsoft Store—apps won't download, updates fail, or the store...

You open Chrome, try to visit a secure site, and see an error like ERR_SSL_PROTOCOL_ERROR

You try to unlock a BitLocker-encrypted drive, but instead of a prompt for the recovery key, you ...