Checklists for software errors, setup, and tool workflows.

How to Create a New Branch from a Detached HEAD in Git

If you see a message like "You are in 'detached HEAD' state" in Git, it means you...

Fix Firefox Secure Connection Failed Due to Proxy Settings

If you see "Secure Connection Failed" in Firefox and suspect a proxy is involved, you'...

Fix Git SSL Certificate Problem on Corporate Networks

If you see git SSL certificate problem: unable to get local issuer certificate while...

Fix Python Permission Denied When Installing Virtualenv with Pip

When you run pip install virtualenv and see a Permission denied err...

Fix Nginx Permission Denied for SSL Certificate Files

When nginx refuses to start or reload with a "permission denied" error related to an SSL ...

Fix npm ERR! enoent ENOENT: package.json Not Found in node_modules

You run npm install or npm start and get something like:

...