Knowledge base for software setup, errors, and daily tool work.

Chrome Certificate Error Invalid Authority: Diagnosis Checklist

When Chrome shows NET::ERR_CERT_AUTHORITY_INVALID and refuses to load a site, it...

Fix Git 'index.lock file exists' Error

If you see fatal: Unable to create 'path/.git/index.lock': File exists. when...

Fix Nginx 'upstream connection refused' When Talking to PHP-FPM

You're seeing upstream connection refused in your Nginx error log, and your site...

Fix Chrome Freezing on Startup on Mac

If Chrome freezes or becomes unresponsive immediately after you open it on your Mac, the problem ...

npm run build Failed: Troubleshooting Checklist

When npm run build fails, the error message can be cryptic. This checklist walks thr...

How to Fix Python Requests Connection Timeout Errors