Checklists for software errors, setup, and tool workflows.

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Latest checklists

If you see connect() failed (111: Connection refused) or connect() failed (13:...

Setup Cloudflare Origin Certificate for Nginx
If you use Cloudflare as a reverse proxy, enabling HTTPS between Cloudflare and your Nginx server...

Fix VS Code Terminal Not Opening PowerShell
If you click the terminal panel in VS Code and nothing happens, or it opens a blank shell instead...

Node.js Heap Out of Memory Troubleshooting Checklist
When a Node.js process crashes with FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - Ja...

Fix Firefox Secure Connection Failed DNS Error
You try to visit a website in Firefox and see 'Secure Connection Failed' with an error li...

How to Manually Remove a Stuck Git index.lock File
If Git operations suddenly fail with an error like fatal: Unable to create 'path/.git/i...