Checklists for software errors, setup, and tool workflows.

How to Fix Cloudflare Origin Certificate Validation Failed

If you see a "validation failed" error when setting up or using a Cloudflare Origin Certi...

Fix Git SSL Certificate Problem: Unable to Get Local Issuer

You run git clone https://example.com/repo.git and get:

fatal: unable to acc...

Fix VS Code Terminal Not Working After Update

After a VS Code update, the integrated terminal may fail to start, show a blank window, or displa...

Fix Git Authentication Failed in VS Code on Linux

You're working in VS Code on Linux, try to push or pull, and get a popup: "Git authentica...

Fix Git Push Rejected Non Fast Forward Error

You try to push your local commits to a remote repository and get: ! [rejected] —

Fix Nginx Upstream Connection Refused in Docker

You have Nginx running, either on the host or in a container, proxying to another Docker containe...