My network connections folder was empty, my wireless icon gone, I could still connect to networks i had previously but new ones were not coming up or at least i couldn't bring up any list. I didn't do much to fix it but followed the tips here
http://support.microsoft.com/kb/313242 and even though it said my drivers and what not were updated already and running fine, all the sudden my icons came back, like they just needed a nudge or wanted someone just to check on them. In any event i registered just to share this as it drove me nuts for 2 weeks. Good Luck.