Checklists for software errors, setup, and tool workflows.

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Latest checklists

If you turned off hardware acceleration in Chrome and now see a black screen, you're not alon...

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

Fix Windows 11 Installation Assistant Stuck at 99%
You're upgrading to Windows 11 using the Installation Assistant, and it gets stuck at 99% for...

Fix Cloudflare Wildcard Subdomain Origin Server Errors
You set up a wildcard DNS record in Cloudflare (e.g., *.example.com) pointing to you...

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

Pip Externally Managed Environment Error: Causes and Fixes
When you run pip install and get the error error: externally-managed-environme...