[Samba] Joined machine cannot mount share, others can - strange

[Lars Hanke]

I run a Samba4 AD and joined a Synology NAS running Samba 3.6.9. I can 
access the shares using smbclient or mount -t cifs from all Linux 
machines (usually running Samba 3.6.6 clients). I can mount the shares 
from WinXP home and Win7 home.

However, with a Win7 Ultimate machine joined to the AD most of the time 
it doesn't work. I can logon to the machine with my AD credentials, but 
I am prompted to re-enter credentials for the shares, which I'd expect 
to just work since I'm logged on to the Domain. And of course the 
freshly entered AD credentials are also rejected.

Most of the time it doesn't work means: I've seen it working, but in 
general it fails.

Thanks for your help,
  - lars.