Printers that use ports that do not begin with COM, LPT or USB are not redirected in a remote desktop or terminal services session. To force all ports to be redirected, the filtering type has to be changed. This is done in the registry.

Do a Start, Run, type in regedit and press Enter. This starts the Registry Editor. Navigate to the key: HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\Default\AddIns\RDPDR. Right-click in the right pane, choose New, then DWORD value. Name the value FilterQueueType, press Enter. Double-click the newly created entry, and set the value to  ...