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On some friends of mine computers, they start out working fine with the wireless network, but after a couple hours or so all of a sudden it isn't able to get online. It's able to maintain a connection if already present, like AIM, but Internet Explorer and other programs like that can't get online. I've tried "repairing the connection", unplugging the card and plugging it back in, going to command prompt and renewing ip address, closing wireless connection and then turning it back on. The only solution is to completely restart the computer, that I'm aware of thus far. Any guidance?

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