Problems with the key file

If your screen looks like this 

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: UNPROTECTED PRIVATE KEY FILE!                 @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
Permissions 0660 for '/home/cgaucho/.ssh/id_ed25519' are too open.
This private key will be ignored.
bad permissions
Permission denied (publickey).
fatal: Could not read from remote repository.

What this usually means

Your SSH key file permissions are too open, so GitHub refuses to use the key.

This often happens when a key was created in one Jupyter session and then used in a later session.

How to fix it

  1. Run these commands in your terminal:
chmod 700 ~/.ssh
chmod 700 ~/.ssh/*

Try again

Rerun the same Git command you tried before (for example, your git clone or git push command).

Reassurance note

Do not worry about the word ‘fatal’. In this case, it usually just means Git stopped because the key setup needs to be fixed.