This one kept me wondering, so I thought I might save people some trouble. If you change your system to use a TMPDIR environment variable, you'll find that samba will use that path for making temporary files with the guest account. Of course this wont work since the main reason people use TMPDIR is to point it to a private directory that no other account can access (/tmp/root, or /root/tmp with 700 permissions in this case) Is there a way to override this path in the smb.conf file itself? I tried making an [IPC$] entry with what testparm showed me was the defaults, only overriding the path, but it didnt work. The workaround at the moment seems to be to set TMPDIR to the path of your guest account that samba is using, before loading smbd/nmbd. - lv