Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You're running a Python script that reads a file, and it crashes with MemoryError

Fix Nginx 502 Bad Gateway: Upstream Connection Refused
If you're seeing a 502 Bad Gateway error with "upstream connection refused" in your N...

Fix Git SSL Certificate Problem on Corporate Networks
If you see git SSL certificate problem: unable to get local issuer certificate while...

Fix Node.js Heap Out of Memory Error in PM2
If you're running a Node.js application under PM2 and seeing FATAL ERROR: CALL_AND_RETR...

Fix Docker Compose 'port 8080 already allocated' Error
When running docker-compose up, you may see an error like Error: Port 8080 is ...

Windows 11 WiFi Has Internet but Other Devices Work Fine
You're connected to WiFi on your Windows 11 PC, but the network icon shows 'No internet&#...