Fix Windows Defender 404 Not Found Error on Windows 10
You click to open Windows Defender Security Center and see a 404 page, or the Settings app shows ...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listHow to Fix Windows Activation Update Error 0x800f0922
You might see error 0x800f0922 when Windows tries to install a feature update or during activatio...
Fix OneDrive SSL Certificate Error and Permission Denied
When you see an SSL certificate error or a permission denied message in OneDrive, syncing stops. ...
Firefox Not Responding? Try Safe Mode Troubleshooting Steps
If Firefox stops responding—freezing, crashing, or refusing to load pages—it's often due to a con...
Fix PowerShell Execution Policy Restricted Error
When you try to run a PowerShell script and see an error like “cannot be loaded because r...
How to Speed Up Slow Windows Defender Scans
If Windows Defender is taking hours to run a scan, you're not alone. The built-in antivirus can s...
Topic paths
Quick titles
How to Reduce Windows Security CPU UsageHow to Restart Windows Defender ServiceFix OneDrive High CPU on StartupHow to Resolve Permission Denied in Windows TerminalTransfer Chrome Profile Between MacsTroubleshooting OneDrive Access DeniedPowerShell Invoke-Command Timeout TroubleshootingTask Scheduler Proxy Sync Troubleshooting