network problem on desktop with xp and laptop vista

i have a desktop with xp connected to a wlan router with a hd network
connection

on that computer i can't find that hd? also not with the software i got
from the hd...
(on the laptop i can connect it with the software)

How can i see the hd without that program? how can i see this with explorer?
or network connection?

Same question for the laptop with vista?
I have to connect the hd with the software but how can i see it on explorer
or networkconnection without the software?

i hope it is possible to get some answers to solve the problems