Windows Defender 502 Bad Gateway: Troubleshooting Checklist
If you see a 502 Bad Gateway error when opening Windows Security or trying to update Windows Defe...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listHow to Fix Windows Activation Token Expired Error
If you see the error 'Windows activation token expired' when trying to activate Windows, it usual...
Fix Windows Search Error 0x80004005 (Crashes)
If Windows Search keeps crashing and shows error 0x80004005, search results stop appearing or the...
Fix OneDrive Sync Invalid Configuration Permission Denied
You open OneDrive and see an error like "Invalid configuration" or "Permission denied" when tryin...
Fix Chrome Not Working with Proxy on Ubuntu
You configured a proxy in Ubuntu, but Chrome ignores it or throws connection errors. This often h...
Fix Windows Command Prompt Access Denied Error
You open Command Prompt, run a command, and get an 'access denied' error. This usually means the ...
Topic paths
Quick titles
How to Solve SSL Certificate Error in Windows SearchTroubleshooting OneDrive Sync Setup Connection RefusedHow to Fix Windows Activation Login LoopCommand Prompt Not Opening as Administrator: FixesWindows 11 Automatic Backup Setup GuideTask Scheduler 504 Timeout: Causes and FixesFix Windows Defender Stuck in Login LoopHow to Backup and Restore Chrome Profiles