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

Fix Windows Security Service Unavailable Permission Denied

You open Windows Security and see 'Service unavailable' or 'Permission denied'. The app may not o...

How to Fix '404 Not Found' File Path Errors in CMD

Fix Windows Update Stuck at Blank Screen During Automatic Repair

You're running Windows Update, and after a restart, the screen goes blank—no cursor, no logo, jus...

Fixing Cloudflare Tunnel DNS Errors: A Practical Guide

If you're seeing DNS errors when using Cloudflare Tunnel (cloudflared), the tunnel might be conne...

Fix PowerShell 502 Bad Gateway After Windows Update

After a recent Windows update, you may encounter a 502 Bad Gateway error when using PowerShell to...

Windows Defender Authentication Failed: Step-by-Step Checklist

You open Windows Security and see 'Authentication failed' when trying to use Windows Defender. Th...