[Samba] homes in Samba 3.5

[Fabian Cenedese]

Hello

I know that this is about outdated Samba versions, but I have
to stick with those. And after trying now for days without getting
anywhere I'm looking for help from others.

We used an old Thecus-NAS as fileserver (no domain etc). It uses
a Samba 3.0.26 which works as we want. Now we bought newer
NAS-boxes, but those too use old Samba versions, 3.5.19.
This in itself is not disturbing but unfortunately the user database
doesn't seem to work anymore.

Previously (only most important settings):
[global]
passdb backend = tdbsam
guest account = nobody
map to guest = Bad User
workgroup = NAS
security = user
force user = root	#  because of other shares besides homes
force group = staff
null passwords = yes

[homes]
comment = Home Directories
force user =
create mask = 0700
directory mask = 0700
browseable = no

Now trying the same settings on the Samba 3.5 doesn't work.
Either I can access all shares or none at all. I played around
with several settings like
[global]
private dir = /raid/data/config	# for backups
#auth methods = guest sam
#password server = *
#force user = root

[homes]
#force user = %S
#valid users = %S

However I just can't get it to work the way it is described in
several examples on the internet or just the way it used to
work. Connecting from a Windows (from XP to 10) I get asked
for username and password. But even giving those credentials
no access is granted. The strange thing is that the user name
is found in the system passwd and the correct home path is
used. In the logfile (level 10) I see:

smbd/service.c:996(make_connection_snum)
  canonicalize_connect_path failed for service testuser, path /raid/data/USER/testuser

And the home directory rights are correct (synched from the old server):
drwx------   14 testuser     staff         4096 May  6 13:05 ./

But unless I use force user = root I can't access it.
What else can I try? Do the workgroups of server and clients have to
be the same (no domain server)?

Thanks

bye  Fabi