Check the following:
When you configure Novell Samba, the Base Context for Samba Users must be set at or above the context where the User objects for Samba have been created.
If you have installed Samba and need to modify the Base Context for Samba Users setting on your server, follow the instructions in Section B.2.4, Changing the LDAP Suffix.
Samba users must be created in a container or partition that has a Samba-qualified password policy assigned to it.
Samba users must be members of a LUM-enabled group.