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

Git index.lock File Exists Even After Deleting: Fixes

You delete the .git/index.lock file, but Git still says it exists. This can happen d...

Recover Lost Commits After Git Detached HEAD

You've made commits while in a detached HEAD state, and now you can't see them on any bra...

Fix Nginx 502 Bad Gateway on Docker Ubuntu

How to Fix Cloudflare 521 Error with Wildcard Subdomains

If you're seeing a Cloudflare 521 error on a wildcard subdomain (e.g., *.example.com), the or...

Fix Windows Security App Not Opening Command Prompt

You click the Windows Security icon or try to launch it from Settings, but nothing happens. Or pe...

Fixing Nginx Permission Denied on Mounted Drive

When you mount an external drive and point Nginx to serve files from it, you may get a 403 Forbid...