Hi.
To connect a printer, user must be added to “lpadmin” group.
Please check if user is added to this group.
To check it please log into this user: su <username>, then type “groups”.
You can also check it in group file: /etc/group.
To add user to “lpadmin” group just execute folowing command: sudo usermod -a -G lpadmin <username>
If this doesn’t help, please give us more information.
1. Client and server NoMachine subscription and version
2. Client and server operating systems.
3. Where the printer is connected to? (Client, Server)
4. The printers is attached by usb or lan?
5. Please describe the route connecting the printer.
(You are trying connect printer TO Debian 7 from other PC, or share printer attached to this Debian?)