Go to the command prompt (start > run > cmd ) type ipconfig/release , than ipconfig/flushdns .
Than open your network connections and go to your present LAN card and disable it.
Than right click on " my computer" and go to properties.
Go to device manager and find your network card and re-enable it.
Wait about 20 seconds than go to the command prompt again and type ipconfig/renew.
Give that a shot. Thats what i have to do daily, something wrong with vista and their DhcpConnDisableBcastFlagToggle bullS#!t...

Anywho hope that helps
