I had a similar problem with Vista printing. I seems that Vista will sometimes see the network drive/shares from other computers other times just won't bother. Even when it does see the shares it often suddenly reports "unable to connect to directory" even though it shows in explorer, just a c**p OS.
The only way I could get it working was to revert to DOS type commands.
I used the net use command i.e.
net use lpt2: \\host\printershare
Once that was successful, installed the printer driver on Vista and pointed at the lpt2 share.
It worked without error, that after a couple of hours of frustrating windows menu system had failed to get anything going.
Mind you next time I use it it will probably give me an error. Windows printing has always been poor, takes a lot of resource.
P Mills
Gatwick Aviation Museum - Charlwood