I have two external hard drives which haven't had a single problem. I added a third external hard drive which seemed OK at first, but then after an hour or so, the computer didn't recognize it and asked me which program I'd like to use to open it. I thought it crashed, so I returned it and got a different brand. I got a Seagate FreeAgent, set it up using the same USB port, and it did the same thing. It was fine at first, but a day later the computer asks me which program I'd like to open it with. I changed USB ports, but it still does the same thing.
The confusing thing is, since I returned the hard drive for a larger one, I assigned it to receive recorded TV. I can still watch the recordings through my Media Center, and it continues to record on it without any problems. I can access its properties in My Computer, but I can't open it.
So what's going on?

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