How can I fix windows defender offline scan flashing a blue screen for a split second on restart

Question

I downloaded something that contained unusual anti virus programs which I believe I uninstalled all of them. After doing so I opened windows defender and ran a full scan with 1 threat which I removed from my pc. I then tried running offline scan through windows defender. It restarted my pc like normal then my screen flickered a blank blue screen then restarted again. My question is how can I fix this issue on offline scan not working? Thank you

Answer 1

Hi Cameron Boukal, this is Henry. I'd like to share some insights regarding the issue.

The third-party antivirus programs you previously uninstalled have likely caused corruption in the Windows Recovery Environment (WinRE). This specialized environment is responsible for running offline scans, and the flashing blue screen suggests that it’s failing to load properly. Rebuilding the Recovery Environment is a solution I recommend to address this issue.

This process forces Windows to rebuild the environment with fresh, correct files.

1. Open Command Prompt as administrator.
2. In the command window, type the following commands, pressing Enter after each one:
   1. reagentc /disable
   2. reagentc /enable
3. You should see a message confirming the operation was successful. Now, restart your PC and try the Windows Defender Offline scan again. It should now boot into the scan correctly.

If that fails, run these two additional commands in the same administrator command prompt to repair any underlying system files, then try the reagentc commands again:

• sfc /scannow
• DISM /Online /Cleanup-Image /RestoreHealth

Hope this helps you.