SSH Private Key Permissions using Git GUI or ssh-keygen are too open
There is a bug with cygwin's chmod, please refer to:
chgrp -Rv Users ~/.ssh/* chmod -vR 600 ~/.ssh/id_rsa
You changed the permissions on the whole directory, which I agree with Splash is a bad idea. If you can remember what the original permissions for the directory are, I would try to set them back to that and then do the following
cd ~/.ssh chmod 700 id_rsa
inside the .ssh folder. That will set the id_rsa file to rwx (read, write, execute) for the owner (you) only, and zero access for everyone else.
If you can't remember what the original settings are, add a new user and create a set of SSH keys for that user, thus creating a new .ssh folder which will have default permissions. You can use that new .ssh folder as the reference for permissions to reset your .ssh folder and files to.
If that doesn't work, I would try doing an uninstall of msysgit, deleting ALL .ssh folders on the computer (just for safe measure), then reinstalling msysgit with your desired settings and try starting over completely (though I think you told me you tried this already).
Edited: Also just found this link via Google -- Fixing "WARNING: UNPROTECTED PRIVATE KEY FILE!" on Linux While it's targeted at linux, it might help since we're talking liunx permissions and such.