Chris,
Sorry that you are seeing this issue. This looks like an issue with the SSH key.
Please take a look at these links and check if any of the suggestions help :
https://bugs.eclipse.org/bugs/show_bug.cgi?id=463793
http://stackoverflow.com/questions/6851461/java-why-does-ssl-handshake-give-could-not-generate-dh-keypair-exception
Can you please try the operation from the command line and check how it works?
Here are the links to the GIT installation and configuration :
https://git-scm.com/book/en/v2/Getting-Started-Installing-Git
https://git-scm.com/book/en/v2/Git-Basics-Working-with-Remotes
If the operation works from command line , please let us know what exact steps you followed along with the version of the JDK configured in MyEclipse to help us replicate the issue at our end. Also please let us know what suggestions you tried from the above mentioned links.
Let us know how it works for you.
–Swapna
MyEclipse Support