First, look to see if you have a root smbuser. Look in /etc/smbpasswd.....you will see all your smbusers.
If root is shown, reset the root smbpasswd by typing smbpasswd at the command line (as root).
Now use root instead of admin on the XP clients.
If no root smbuser is shown, I do the following to add an smbuser:
smbpasswd -a root
then
smbpasswd -e root
You should now have a root user in /etc/smbpasswd
See this thread for further hints or search for 'samba join domain' in the forums.
http://forums.contribs.org/index.php?topic=23427.0There's was a howto for leaving and joining the samba domain by dmay but it seems to have disappered from the howto list.
Good Luck,
Sonny Bertoncini