typical problem is wrong permissions on files in .ssh folder on server or client. safest way to copy pub key to server is to use ssh-copy-id command, this will set proper permissions on authorized_keys file (either 600 or 640 if i remember right)

check /var/log/secure for ssh log on server.

typical problem is wrong permissions on files in .ssh folder on server or client. safest way to copy pub key to server is to use ssh-copy-id command, this will set proper permissions on authorized_keys file (either 600 or 640 if i remember right)

you can also try increasing verbosity as

ssh -vvv user@vpshost