Computer freezing when connecting to the Wifi access point

I am trying to set up a wifi network..already installed
the PCi card in a Desktop computer running windows XP, but
after installing a PCMCIA in wondows 98 .. when I tell the
PCMCIA to connect to the access point the computer freezes
and the only way to re-booting the computer again is
removing the PCMCIA card from the socket...

By the way the card installation has been done couple
times..and it is recognized by the system... if not close
to the wifi access point or other wifi card.. it works
fine...

Whats wrong?