Checklists for software errors, setup, and tool workflows.

How to Fix Nginx Upstream Connection Refused on Port 80

When nginx logs show "upstream connection refused" while connecting to port 80, it means ...

Windows Update Service Troubleshooting Checklist

When Windows Update stops working, the update service itself is often the culprit. You may see er...

Fix Nginx 502 Bad Gateway on Docker Ubuntu

You're running Nginx as a reverse proxy inside Docker on Ubuntu, and suddenly you see

Nginx Redirect Loop Not Working: Causes and Fixes

You've set up a redirect in Nginx, but instead of landing on the intended URL, the browser sh...

How to Fix Nginx 502 Bad Gateway in Docker

If you're running Nginx as a reverse proxy inside Docker and seeing a 502 Bad Gateway error, ...

Fix Nginx Permission Denied for Static Files

Common Causes

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