Unable to find existing network and broadband!!

I have had a wireless network for some time now, from a
company called Xyxel in Norway. It worked fine, but my usb
antennae in a usb 1.0 port was on the slow side.
Therefore i decided to upgrade to a
"Microsoft Broadband Networking Wireless PCI Adapter MN-
730"
Once i had installed the software, and then installed the
hardware as the directions stated. I got on the busyness
of installing the network. I selected the option of
already existing network from another company than
Microsoft, and it proceeded to find my network.
This is where the problems started, it found the network,
but not our adsl connection, which is sendt through the
wireless hub. So i rstarted the computer and the network,
and started uo the brouadband utility again. This time it
found neither the internet nor the network. I was
completely lost. My other computer which still has the old
usb stick has both the network and the internet.
It then told me my network had no WEP security. But this
was never an issue before. Every time i went into the msXP
tool panel, and told the computer to connect to the
network even though it was insecure, it desconnected
instantly.
What should i do? Should i install the WEP key, and if so
how?
In advance thanks.