After restoring from a time machine backup using migration assistant I can't log in

Hi, I recently bought a Mac Pro and using a Mountain Lion boot disk I made installed a fresh ML install which went fine. During the final part of install it gives you the option of restoring user data etc etc from a time machine backup which I have from my MacBook Pro which again in principal went fine until I went to log in when I got the message 'An error has occurred unable to log into this account a this time'.

Looking on the web I thought at first it was a password issue so restarted with command-r and reset the password, however the same error still occurs. I don't think it is password issue as if you deliberately enter the wrong password it rejects it immediately where as with the correct password it hangs for about 15secs before throwing up the above error.

Can anyone offer any advice?

The only thing I can possibly think of is that on my MBP where the time machine backup is from my home folder is on a 2nd HDD that is not the boot disk and I only have a single HDD on my MacPro.......