GitHub Error: Key already in use

I have created two GitHub accounts. One for my work user and one for my personal self. I needed to do catch up on some work and as such cloned my work repo onto my personal PC. In order to do simple "git push origin master" commits without entering my username and password the whole time I simply want to add my public key from my home pc to the work repo. However Github gives this error:

Error: Key already use

After a bit of Googling I came across this link which states "To resolve the issue, remove the key from the other account or repository and add it to your account" Of course there is a duplicate key as I've added my home public key to github so that I can code on my own personal projects. After all I want to be able to code to my work repo using both my work pc and personal pc.

How can you add multiple "same" public keys without Github throwing that error and also why in the world, is that error thrown in the first place?


You can create one more key pair, say id_rsa_personal.pub, and add it to the Github account.

Next, create/edit the .ssh/config file.

# Default GitHub
Host github.com
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_rsa

Host github-public
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_rsa_public

Host github-personal
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_rsa_personal

The above file will help you to use more than one Github account. For background info, refer to the answers to this question.

Next, you will need to alter your .git/config remote url to point to:

git@github-personal:<gh_username>/<gh_reponame>.git

Rather than the usual:

[email protected]:<gh_username>/<gh_reponame>.git


The key could be already in use on other github projects as deploy key, that's a bit tricky to find but run:

ssh -T -ai ~/.ssh/KEY_NAME [email protected]

change KEY_NAME with the name of your SSH private key and you will be good to go

from: https://help.github.com/articles/error-key-already-in-use/#finding-where-the-key-has-been-used


John commented that it didn't work for him.

Perhaps the step you're missing is you need to alter your .git/config remote url to point to git@github-personal/<reponame>.git etc.. rather than the usual [email protected]/<reponame>.git