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I have a new Laptop, The first day I got it I hooked it up to the internet using a
Motorola SB5101 SURFboard(R) Cable Modem, and I had unhooked it for travel
purposes. When I hooked it back up, it wouldn't detect my modem.
Hmm...Is that modem for the laptop wireless or wired? If it is wired, then maybe there is dust in the port. If it is wireless, check to see if there is any interference between the modem and the wireless hub.
Possibly, the modem may have suffered damage if you took it on your travel. All I can say is check the FAQ for it (either the web or the manual you got for it) and try troubleshooting the problem.