Old thread but this is for reference;
Let 7 detect the usb device and install it's basic
drivers. The Installation disk that comes with this unit is useless on 7, skip it. The current linksys - cisco support page for this unit is a joke, but you can d/l the 7 32/64 drivers. There is no auto install. Unzip the files into your d/l folder.
Then r-click computer and go to manage - then device drivers. Expand your network adaptors, you'll see your adaptor there. R-click on your adaptor go to properties. You'll see a
driver tab, click on that. You'll see an update driver tab in that window. Click on that, select browse to the folder that contains your updated drivers, OK and let 7 do it's thing.
The jury is still out on the wusb100's quality but remember it's a cheap usb adaptor. You can find alot of post with people using these with problems on Vista as well as XP. Your routers settings & security can have alot to do with how well it plays nice or not.