Checklists for software errors, setup, and tool workflows.

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Latest checklists

You try to push your local commits to a remote repository and get: ! [rejected] —

You're reading a file in Python and hit UnicodeDecodeError: 'charmap' codec can...

Fix 'Permission Denied' in VS Code Terminal for Node.js
You're working in VS Code, run npm install or node app.js, and get ...

Nginx Upstream Connection Refused: Diagnosis and Fixes
When Nginx returns a 502 Bad Gateway or logs "upstream connection refused", it means Ngin...

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...

How to Fix Git 'index.lock' File Exists Error
When you see fatal: Unable to create 'path/.git/index.lock': File exists., G...