I have a Samba print share set up, with a "print command" specified that just 'cat's the file to /dev/ulpt0. The share is accessed by the guest Samba account, which I have set to be the 'smbguest' username. I can manually run the print command as root, and the file prints. I can manually run the print command as 'smbguest' (through sudo) and the file prints. Therefore, I know the printer hardware is set up correctly. However, when run the command through Samba itself (by printing over the network from another machine), I get: cannot create /dev/ulpt0: Permission denied which is the same message I would get if I don't have write permissions to the device. NOTE: I have recently done an upgrade of samba (might have been from 3.5, but I think it was an earlier 3.6.x - I can track that down if it's important). In the previous version, everything was working. The device itself has the following permissions: $ ls -l /dev/ulpt* crw-rw---- 1 root print 0, 142 Aug 5 22:31 /dev/ulpt0 The 'smbguest' account is in the 'print' group, as evidenced below: $ groups smbguest smbguest smbguestgroup print so it should be able to write to ulpt0. In fact, it can, when the command is run through sudo -u smbguest ... Further, if I change permissions on the device to, for instance, have a group of 'smbguest', everything works. Also, if I change permissions on the device to have read/write for the 'other' users, again everything works. I do not want to put that in place permanently, of course. I have found that when the Samba 'print command' itself is run, the group membership *only* includes the 'smbguest' group. I altered the print command to write a log message including the output of `id`, for instance, and it only includes the 'smbguest' group, rather than the above three groups. NOTE: I have tried using 'force group = print' as a workaround, but that does not seem to have any effect for me. I don't know if that ever worked, because I had no reason to try, before. I am happy to provide additional information if needed.