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

Cloudflare Error 521: Web Server Down Checklist

Cloudflare error 521 means your origin web server refused the connection. This is not a Cloudflar...

Fix Cloudflare Origin Certificate with Let's Encrypt

If your origin server is rejecting the Cloudflare origin certificate—perhaps because of a SAN mis...

How to Fix Git Merge Conflict Permission Denied Errors

Fix Firefox Secure Connection Failed Due to Proxy Settings

If you see "Secure Connection Failed" in Firefox and suspect a proxy is involved, you'...

How to Push a Git Detached HEAD to Remote

You're working on a Git repository and realize you're in a 'detached HEAD' state....

Fix Nginx Upstream Connection Refused Error

When Nginx returns upstream connection refused in your error logs, it means Nginx tr...