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

Nginx Upstream Connection Refused: Diagnosis and Fixes

When Nginx returns a 502 Bad Gateway or logs "upstream connection refused", it means Ngin...

Cloudflare Origin Certificate Setup for Apache

If you use Cloudflare's proxy (orange cloud), you can set up an origin certificate to encrypt...

Fix 'package.json Not Found' After Cloning a Repository

Symptom

You clone a repository from GitHub (or another remote), change into the directory...

Chrome Certificate Error Invalid Authority: Diagnosis Checklist

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

Fix Chrome Status Access Violation by Disabling Hardware Acceleration

If you see a STATUS_ACCESS_VIOLATION error in Chrome, it usually happens when th...

Fix Windows Explorer Restarting After Software Install

If you've just installed a program and Windows Explorer starts restarting repeatedly—taskbar ...