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

Cloudflare Wildcard Subdomain CNAME Setup Guide

If you need to route all subdomains (e.g., *.example.com) to the same target, a wildcard CNAME re...

Cloudflare SSL Full Strict: Fix Origin Certificate Errors

If you've set Cloudflare's SSL/TLS encryption mode to Full (Strict) and started seeing er...

Docker Compose Secret vs Environment Variable: When to Use Each

If you're writing a docker-compose.yml and wondering whether to put a value in <...

Fix Nginx Permission Denied for Static Files

Common Causes

When Nginx returns a 403 Forbidden or 'permission denied' error for...

Fix npm run build Failed Due to Missing Dependencies

When you run npm run build and it fails with errors about missing dependencies, the ...

Fix Windows Update Error 0x80070002: Missing File

If you see error 0x80070002 when running Windows Update, it usually means the system cannot find ...