garrstim,
Did you install the card while logged in as "Administrator"? If so, this SHOULD work. Check out the technotes on installing this card at:
http://linksys.custhelp.com/cgi-bin/...=5603644608B02.
It's possible that you installed it as another user with Admin rights, but that user has NTFS permission restrictions preventing the drive from being shared by other users. I would press CTRL-ALT-DEL, type Administrator and login with the Administrator account/password when installing this device.
- John