[Samba] erratic behaviour with valid users = +group

[Roel van Meer]

Klaus Hartnegg writes:

> I have a unix group for admin users, and shares with
> valid users = +smbadmin
> admin users = +smbadmin
>
> Sometimes this works, sometimes Windows reports system error 5.
>
> Last week I thought that this affects only the group mapped to rid=512, but  
> now I notice that it affects all unix groups, just not always.

Which version of samba are you using?
Perhaps this is related to bug 9570, which was fixed in 4.1.12.
See https://bugzilla.samba.org/show_bug.cgi?id=9570

Regards,

Roel