Checklists for software errors, setup, and tool workflows.

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Latest checklists

If you see fatal: Unable to create 'path/.git/index.lock': File exists. when...

You run git push and get: ! [rejected] main -> main (non-fast-forward) erro...

Fix 'git remote add origin already exists' Error
When you run git remote add origin <url> and see fatal: remote origin al...

Fix Windows 11 Installation Assistant Stuck at 99%
You're running the Windows 11 Installation Assistant, it reaches 99%, and then sits there. No...

Fix Nginx Upstream Connection Refused Timeout Error
When Nginx returns 502 Bad Gateway or logs upstream connection refused timeout...

Cloudflare SSL Full Strict Troubleshooting Steps
If you have set Cloudflare SSL/TLS encryption to Full (strict) and your site shows errors like 52...