Fix Windows Defender Not Opening Error 404
You try to open Windows Defender and get an error 404 – the page or resource can't be found. This...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listNginx 502 Bad Gateway: Troubleshooting Checklist
If you're seeing a 502 Bad Gateway from nginx, it usually means nginx can't reach the upstream se...
How to Fix Edge Update Error 0x80070643
When updating Microsoft Edge, you may encounter error 0x80070643. This usually indicates a proble...
Windows Terminal Blank Screen: Diagnostic Checklist
You launch Windows Terminal and see nothing but a blank window—no cursor, no prompt, just an empt...
Fix Windows Defender Mac Compatibility Issues with Antivirus
If you run Windows on a Mac via Boot Camp, Parallels, or VMware Fusion, you may see warnings that...
How to Fix Windows Search 504 Gateway Timeout Error
If you're seeing a "504 Gateway Timeout" error when using Windows Search, it usually means the se...
Topic paths
Quick titles
Collect Windows Update Logs for TroubleshootingWindows Activation Proxy Error: Complete Troubleshooting ChecklistResolve Port Already Allocated for Windows UpdateHow to Fix SSH Permissions and Ownership IssuesWindows Terminal Keeps Crashing After Update – FixWindows Defender Not Opening on Windows 11: How to FixPowerShell Network Error Checklist: Common FixesWindows Search Connection Refused Error Fix