Cannot log into Forge SSH

I have a database server on a Digital Ocean server that holds all my databases but I had to reinstall osx and after Installing Sequel Pro I cannot access the DB server. I've checked and double-checked the details and all are exactly the same as my details on the MacBook. The only thing different will be the SSH keys. I created new keys on the iMac but if I add the key to Forge and try to log in I get

Unable to connect to host 00.00.00.00, or the request timed out.

Be sure that the address is correct and that you have the necessary privileges, or try increasing the connection timeout (currently 10 seconds).

MySQL said: SSL connection error: Server doesn't support SSL

If i play around then i get::

The SSH Tunnel could not authenticate with the remote host. Please check your password and ensure you still have access.

Now i know the password is correct as i can login to the server through SSH and also connect to the db using the same details.

I just can't understand why it works on my MacBook and not on the iMac with exactly the same settings...

Any help or ideas would be massively grateful.

Thank you