[Anonymouse]

If you usually put the PC to sleep or in hibernation rather than completely shutting down, a quick reboot can resolve the problem. This is a known issue with Vista and there doesn't yet seem to be a definitive solution.

Vista does seem to have a habit of forgetting things, such as Internet connections and Explorer settings, so you sometimes have to remind it. My sister's PC forgot last week it had a printer, and it wasn't until I logged into the Administrator account (intending to reinstall it if necessary) that the damn thing suddenly thought 'Oh, there it is! Better reinstall it quick!' and it did. There's no love lost between those two, I tell you...

There might be something here that'll help with your connectivity issue.