The most common errors that can afflict Windows networking systems include:
Incorrect IP address.
Incorrect or inconsistent netmasks .
Incorrect router address.
Incorrect DNS server address.
Incorrect WINS server address.
Use of a Network Scope setting ” watch out for this one!
The most common reasons for which a Windows NT/200x/XP Professional client cannot join the Samba controlled domain are:
smb.conf does not have correct add machine script settings.
" root " account is not in password backend database.
Attempt to use a user account instead of the " root " account to join a machine to the domain.
Open connections from the workstation to the server.
Firewall or filter configurations in place on either the client or on the Samba server.