Checklists for software errors, setup, and tool workflows.

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Latest checklists

If you see the error error: externally-managed-environment when running pip in...

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

Fix Firefox Secure Connection Failed Error (Mozilla)
When Firefox shows 'Secure Connection Failed' and a message like MOZILLA_PKIX_ERROR_<...

Fix Git 'index.lock' File Exists Error in SourceTree
If you use SourceTree and see an error message like fatal: Unable to create 'path/to/.g...

Fix 'nginx configuration test failed invalid parameter'
When running nginx -t to test configuration, seeing "nginx: [emerg] inva...

How to Fix Python Unicode Decode Error in Pandas
When reading a CSV or text file with pandas.read_csv(), you might encounter a ...