samba domain registration problem
 

i am knew to linux, i configured samba on a suse 11.4 server, but the issue arises when i try to join the domain with windows 7, it accepts but when i try to log on to the domain, i get an error message like "there are currently no logon servers available to service the logon request".
secondly i also tried to check the option that says "allows smb authentication for linux" but it refused. and on top of that, it changes the domain option form PDC to BDC which is a problem to.
so i need help to allow me log on users to the domain without that error.thank you in advance