Windows Defender after reinstall Windows

michaelajirkaxbox 

Hello! You've posted your question in the Tech Community Discussion space, which is intended for discussion around the Tech Community website itself, not product questions. I'm moving your question to the Windows 11 space - please post Windows 11 questions here in the future. (You can find this and other product discussion spaces in the future through the Community Hubs page.)

Check for Group Policy settings: Open the Group Policy Editor (gpedit.msc) and navigate to Computer Configuration > Administrative Templates > Windows Components > Windows Defender. Look for any settings that might be restricting access to Windows Defender. If you find any, try disabling them or setting them to "Not configured".

If you're using Windows 11 Home (which doesn't have Group Policy Editor), you may need to make changes in the Registry. Note: Be careful when working with the Registry, as incorrect changes can cause issues. It's a good idea to back up the registry first.

Hello,

This is a known issue that appears after reset or clean install.

See if this fix helps you:

https://www.kapilarya.com/fix-cant-access-virus-and-threat-protection-on-windows-security

Hope this helps!

Note: Included link in this reply refers to blog post by a trusted Microsoft MVP.