cannot access files

i have windows ME on a networked machine. overnight i cannot access any files or internet. internet comes up with "active-x controls will not allow you to view this page"."My documents" seems to have dissapeared and most icons off the desktop have gone. I have run Norton on the machine via the network with nothing found. The machine has up to date anti virus and is firewalled on a router. all the files are there and can be accessed via the network..I cannot download adaware as it wont let me on the internet and dont want to run sybot