After getting rid of a trojan a while back I noticed I've been having
some problems with my wireless networks.

The preferred networks area in the wireless network tab of the wireless
network connection properties doesn't list any of the networks I've
added.

Even if I add a new network, it appears there just after I've added it
but after I close the property panel and open it up again it is no
longer listed.

It appears that xp only remembers one network setting, which means
every time I move to a different place I have to add a new network and
provide the WEP key.

Any thoughts on why this is happening and how to resolve it?

Thanks!
Peter