1. 2026.03.27

   "You Have Mail" But No Mail on Mac

   Tools

   macOS login shell says "You have mail." but mail says "No mail." — here's why and how to fix it.

2. 2023.07.08

   SSH Authentication Fails on github.com While Works on Other Servers

   Tools

   DNS pollution leads to authentication failure on github.com

3. 2023.06.28

   VSCode Azure Extension Sign-In Issue

   Tools

   If you are behind a proxy, signing-in Azure services with VSCode is likely to fail.

4. 2022.09.06

   Quick Setup for Certbot

   Tools

   Certbot, good bot.