I´ve upgraded a redhat 8 box from a samba 2.2.7 server to a sama 3.0.4 with ldap (it seems everybody is doing this these days ;-). Config file OK, server loads OK, windos 98 and 2000 log on OK, startup script loads... and some shares cannot be mounted. Trying to access the shares returns "Unknown error 31" (windows 98), "Invalid group" (Windows 2000) and "NT_STATUS_NO_SUCH_GROUP" (smbclient). After several checks I narrowed down the problem to the following (an example): [WIP_Con] comment = comment path = /home/WIP_Con writable = no printable = no browseable = yes guest ok = no valid users = @WIP_Con create mask = 0750 force create mode = 0750 directory mask = 0750 force directory mode = 0750 force group = @WIP_Con write list = WIP_Con The problem above is the @ sign in the parameter "force group". Removing it and reloading the server made the problem go away. It worked perfectly with samba 2.2.7. I´m reporting this because I would like you to update the smb.conf man page, stating that @ signs should not be used with "force group" or make testparm catch this situation, which would be better. Sorry for any spelling errors (I´m brazilian) and feel free to mail-me if you need any other information.
force group should be a group name. That's stated in the smb.conf(5) man page as well as in the example. I think we'll leave it as it is.