I almost ripped my hair off cause is could not get my ADSL modem ( ZTE xsdl modem) given by SLT free of charg, therefore i though of sharing the experience with you'll.
First you have to enable the hidden administrator account on your Vista os. to do this open a command prompt using the right click and select " run as administrator" and type the following :
net user administrator /active:yes
after this restart the computer and log into the computer using this admin account which will display your boot screen.
Use this link to donwload the drivers and then install the 32 bit version of the modem.:
http://rapidshare.com/files/162782188/xdsl.rar.html
Follow the instructions and then restart the computer , before restarting unplug the modem and let the system boot up, then log in using the admin and then plug in the modem, there you will see the exact same thing you got in XP on your Desktop
thanks