Checklists for software errors, setup, and tool workflows.

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Python Module Not Found: Troubleshooting Checklist

You run a Python script and get ModuleNotFoundError: No module named 'something'. Th...

Fix Port Already Allocated Error for Windows Update on Windows 10

You try to run Windows Update but get an error message like 'port already allocated'. This usuall...

Fix Windows Update Error 0x80070002

When Windows Update fails with error 0x80070002, it usually means the update installer can't find...

Fix Windows Security Service Not Running Error

You open Windows Security and see a red banner: “Windows Security service is not running.” Or you...

Fix Command Prompt Not Recognizing Commands

You type a command in Command Prompt and get '...' is not recognized as an internal or exte...

Fixing Windows Defender Authentication Failed Permission Denied
You try to run a Windows Defender scan or update, but get an error like "Authentication f...