[Samba] user both missing and present

[Geoff Crompton]

I'm trying the classicupgrade, and it is crashing out:

ERROR(<class 'samba.provision.ProvisioningError'>): uncaught exception -
ProvisioningError: Could not add member 'S-1-5-21-305843216-174882882-
1673945419-42545' to group 'S-1-5-21-305843216-174882882-1673945419-
1231' as either group or user record doesn't exist: Unable to find GUID
for DN
   File "/usr/local/samba/lib/python2.6/site-
packages/samba/netcmd/__init__.py", line 175, in _run
     return self.run(*args, **kwargs)
   File "/usr/local/samba/lib/python2.6/site-
packages/samba/netcmd/domain.py", line 1318, in run
     useeadb=eadb, dns_backend=dns_backend, use_ntvfs=use_ntvfs)
   File "/usr/local/samba/lib/python2.6/site-packages/samba/upgrade.py",
line 919, in upgrade_from_samba3
     add_users_to_group(result.samdb, g, groupmembers[str(g.sid)],
logger)
   File "/usr/local/samba/lib/python2.6/site-packages/samba/upgrade.py",
line 316, in add_users_to_group
     raise ProvisioningError("Could not add member '%s' to group '%s' as
either group or user record doesn't exist: %s" % (member_sid, group.sid,
emsg))


I've found that the user -42545 does not exist in my samba3 as a user, 
but somehow does exist as a member of the -1231 group.

I'm using the ldapsam passdb backend, and I don't understand how this 
situation has occurred. In my LDAP directory the -42545 user looks just 
like some of my other users (who don't trigger this problem).

What should I do next?

Cheers,
Geoff