Media Disconnected

I recently had to reinstall Windows Vista Ultimate (probably because
of a probleam caused by Trend Micro, but that's another story), but
after about a week I have a new intermitant problem: I loose Internet
connection (via Verizon FIOS). When I check my IPCONFIG in CMD, I get
"Media Disconnected," and I have to reboot. I know the problem is on
my computer because the other computer on my home LAN continues to be
connected. So I tried to restore, but guess what, I had only one
restore point, the last one, which was after I started having these
problems. Anyone have a clue?

TIA,
Martin