Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You're working on a Python project and suddenly get errors like ImportError or <...

You click Check for updates, see 0% for ages, and maybe an error like 'Windows Update service...

If you're running npm on Linux and see npm ERR! enoent ENOENT: no such file or director...

Fix npm run build Failed with PostCSS Error
You run npm run build and see a PostCSS error. This often happens after updating pac...

Fix Firefox Secure Connection Failed Error (Mozilla)
When Firefox shows 'Secure Connection Failed' and a message like MOZILLA_PKIX_ERROR_<...

Fix Git 'index.lock file exists' Error
If you see fatal: Unable to create 'path/.git/index.lock': File exists. when...