[Samba] Account Unknown for users with Samba 3.0.11/14

[James.Cort at u4eatech.com]

Quoting James.Cort at u4eatech.com:

> Hi,
>
> I've got a problem with a samba server I inherited which I can't solve.
>
> I think it's the configuration rather than the version because I have 
> the same problem with a 3.0.14 and a 3.0.11 Samba server with almost 
> identical configurations.  Both authenticate against LDAP, one has an 
> old smbpasswd file which should no longer be in use.
>
> The issue is that when I click "Properties... Security" in Windows on 
> something shared on the samba server, all the groups come up OK but 
> users are displayed as  (for example) "Account Unknown 
> {S-1-5-21-4012146134-3166284455-2856603714-3038)".
>
> I've checked, and that account SID is correct. However, I'd expect it 
> to eventually resolve to a username - it doesn't.

Further investigation has shown that the LDAP server is queried for 
Group SIDs, but not for User SIDs.