Checklists for software errors, setup, and tool workflows.

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Fix Nginx Upstream Connection Refused in Proxy Pass

When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Fix Git 'fatal: refusing to merge unrelated histories' on GitHub
You try to merge two branches in Git, and get fatal: refusing to merge unrelated histories<...

Fix Missing Taskbar Icons in Windows Notification Area
You look down at the notification area (system tray) and an icon you rely on—like volume, network...

How to Turn On Bluetooth in Windows 11: Quick Fixes
You open Quick Settings, click the Bluetooth icon, and nothing happens—or the toggle is grayed ou...

Fixing Nginx 502 Bad Gateway in Docker: Practical Steps
You set up Nginx as a reverse proxy in Docker, but instead of your app you see a 502 Bad Gateway....

Fix Docker Compose 'Port Already Allocated' for MySQL
You run docker compose up and get an error like Error: Port 3306 is already al...

Checklists for software errors, setup, and tool workflows.

Latest checklists

Fix Nginx Upstream Connection Refused in Proxy Pass

Fix Git 'fatal: refusing to merge unrelated histories' on GitHub

Fix Missing Taskbar Icons in Windows Notification Area

How to Turn On Bluetooth in Windows 11: Quick Fixes

Fixing Nginx 502 Bad Gateway in Docker: Practical Steps

Fix Docker Compose 'Port Already Allocated' for MySQL

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