Checklists for software errors, setup, and tool workflows.

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Latest checklists

After a Chrome update, you might see sync paused or error messages. Your bookmarks, passwords, or...

When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Fix Windows Security App Blocked by Antivirus
You open Windows Security (formerly Windows Defender) only to see an error or blank screen becaus...

Fix ERR_CONNECTION_RESET in Chrome on Mac
If you see ERR_CONNECTION_RESET in Chrome on your Mac, the browser cannot establ...

How to Fix Git Push Rejected (Non-Fast-Forward) Error
You run git push and get an error like ! [rejected] main -> main (non-fast-...

How to Fix Nginx Upstream Connection Refused on Port 80
When nginx logs show "upstream connection refused" while connecting to port 80, it means ...