A user connecting to a guest ok = yes samba share needs to have a user name in
the UNIX /etc/password file, if the security is set to server. It seems as
though guest ok = yes does not work. In Samba 2** guest ok = yes worked
properly in that the user did not need to supply a username or password to
access the share. In this case the key (guest account = valid UNIX account)
does not help.
You didn't read the release notes did you :-)
Changes in Behavior
The following issues are known changes in behavior between Samba 2.2 and
Samba 3.0 that may affect certain installations of Samba.
1) When operating as a member of a Windows domain, Samba 2.2 would
map any users authenticated by the remote DC to the 'guest account'
if a uid could not be obtained via the getpwnam() call. Samba 3.0
rejects the connection as NT_STATUS_LOGON_FAILURE. There is no
current work around to re-establish the 2.2 behavior.
If you want to map every connection to guest, then add
a username map entry
nobody = *
*** Bug 576 has been marked as a duplicate of this bug. ***