Checklists for software errors, setup, and tool workflows.

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Latest checklists

You've tried to merge two Git branches and got the error: fatal: refusing to merge unre...

Fix Nginx Upstream Connection Refused Behind Cloudflare
If you see upstream connection refused in your Nginx error logs while using Cloudfla...

Fix Git Push Rejected: Non-Fast-Forward Error
You try to push a commit to a remote repository and get: ! [rejected] main -> main (non-...

Fix VS Code Terminal Not Opening on Mac
You open VS Code, press Ctrl+` or click the Terminal panel, and nothing happens. The...

Fix pnpm Install Failures in CI/CD Pipelines
When pnpm install fails in your CI/CD pipeline, it usually stops the build. The error messages va...

Windows Security App Not Opening: Practical Fixes
If the Windows Security app won't open—clicking the icon does nothing, or it crashes immediat...