Checklists for software errors, setup, and tool workflows.

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Latest checklists

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

How to Fix Nginx Redirect Loop in Server Block
You set up a server block in Nginx, but now the browser keeps redirecting—http to https, or www t...

How to Fix Chrome Sync Error 'Sign In Again'
What the Error Means
When Chrome displays 'Sign in again' in the sync settings, i...

Fix npm run build Failed Due to Missing Dependencies
When you run npm run build and it fails with errors about missing dependencies, the ...

Fix 'docker network not found' After Prune
If you run docker network prune and later see errors like network not found

How to Fix the Git index.lock File Exists Error
You're in the middle of a Git operation—commit, merge, or rebase—and Git stops with: fa...