git push login failure

When you run git push and see something like this.

remote: Support for password authentication was removed …
fatal: Authentication failed for 'https://github.com/…'

Cause

GitHub blocks pushing with a password. You need a browser login (credential manager) or a token.

Fix

If a browser login window opens

Just log in. Enter your GitHub username and password and click Authorize. After the first time it will not ask again.

If no window opens and the terminal asks for a username and password

Git Credential Manager is missing. The quickest way is to ask the Cursor chat like this.

git push fails with Authentication failed. Install the GitHub CLI (gh),
log in with gh auth login, and then push again.

Follow the AI's instructions and enter the code in the browser.

If you are logged in with a different account

This happens on computers that used a different GitHub account before.

• Windows: open Credential Manager from the Start menu → Windows Credentials → remove git:https://github.com → push again.
• Mac: run the following in the terminal, then push again.

git credential-osxkeychain erase <<EOS
host=github.com
protocol=https
EOS