Double check you've got printer forwading ticked on within Remote Desktop

If you've got a .RDP file, right click on it and go edit. If not, just crack open RD as per usual
Ensure options is "expanded" and go to the local resources tab
If the box labeled printers isn't ticked, tick it.
Do not connect just yet..


Crank open the Registry editor

Go start -> Run, type regedit and click ok



Browse to the following..

HKEY_CURRENT_USER -> Software -> Microsoft -> Terminal Server Client -> Default -> Addins -> RDPDR



Within the Key RDPDR, add a new DWORD Value

Call it FilterQueueType (I'm pretty sure it's CAsE sENsiTiVE), and give it a value of ffffffff (8 f's)
Click ok and close down the registry editor



Ensure driver is installed on the remote Computer

Your printer is only going to forward itself to a PC that has a driver installed on it, so download/copy the driver across and install it
Hint: To install a printer driver on a computer without it showing up in the printer list, open up the printers and faxes window, go file -> server properties, go to the drivers tab and then add your printer