IE won't open with WiFi connection

I have a Toshiba Portege' 3500 tablet pc. with built-in
WiFi. I am able to get a good connection but neither IE
or Outlook will connect. It works just fine with my Dell
laptop that I just purchased. I have spent hours on the
phone with both Toshiba Support and Belkin (router)
support but they can't find the problem. Both the router
and wireless card in the computer seem to check out fine.
Can anyone suggest what I might try next?? Many thanks.

Jim