Problems with Notebook Presario C500 y Router Encore

Hello, i've problems with my notebook and my router ADSL, the problem is
that my notebook don't receive IP in the WIFI interface, ie, that the DHCP
Client in Windows Vista don't work with my Router, but ther router work very
good with anothers notebook(Windows 98, XP, Linux) and my notebook work very
good with another router in other site. I'm searching on the web, and i
found that Windows Vista have problems with some
routers(http://support.microsoft.com/kb/930517/es) someone know where
donwload this HotFix. that will revolve the problem ?

Thanks

Pedro C. Arias
Rosario-Argentina.