
How to Fix Windows Defender Not Opening
If Windows Defender won’t open—whether it crashes, shows a blank window, or does nothing when you...
Software troubleshooting desk

If Windows Defender won’t open—whether it crashes, shows a blank window, or does nothing when you...

You open Windows Security and see a blank white or gray screen. The interface doesn't load, and n...

You bought an app on one Windows PC, but it doesn't show up on another. Or your settings aren't s...

If you see activation errors like “Windows is not activated” or “We can’t activate Windows on thi...

You click "Check for updates" in Windows Update, but nothing happens—or the download hangs at 0%....

After a Windows update, you might find that Windows Security (formerly Windows Defender) is missi...