[Samba] guest user (from session setup) not permitted to access this share

[Chris]

The Samba logs have many of the subject's lines::

--------------------------------------------------------------------------
[2005/09/08 15:43:48, 2] smbd/service.c:make_connection_snum(314)
  guest user (from session setup) not permitted to access this share 
(EACM)
[2005/09/08 15:43:48, 2] smbd/service.c:make_connection_snum(314)
  guest user (from session setup) not permitted to access this share 
(EACM)
--------------------------------------------------------------------------

This is on a Debian 3.0.14a system. The one with the problems I reported 
earlier in these posts:

	can't update msaccess mdb file
	log files created for both the hostname and the IP address?

I ran "grep 'guest user' /var/log/samba/*" and virtually every client 
log has many of these entries, with virtually every share, going back 
as far as the logs.

Running the same grep command on 4 other PDC's that I have installed 
(didn't install this one, just trying to troubleshoot) display exactly 
zero instances of such entries.

Help!
What is the "guest user (from session setup)"?

Any ideas why is it trying to access shares from the clients?

What can I provide to help get this problem resolved?

Thank you.

Chris