Setup will not detect the MN 720 in my laptop

I have a MN720, that I am installing on my Dell Inspiron
Laptop, running windows 98SE, and attempting to network to
my newly installed SBC Yahoo DSL Router. When I run
setup, and I get to the point where the software asks me
to insert my card, which I do, the laptop does not detect
the card. I also have a wireless card, that is a Verizon
wireless air card. That card is not installed at the time
I try to install the Microsoft card. Any help would be
greatly appreciated.

Thanks,

Paul Staples