I ran into this at work recently. Go into disk management and see what letter it is trying to map to. What happened with me was I had a c:(hard drive), d:(cdrom), and e:(network map). When I plugged in the USB drive, it would try to use the e:, but it was already in use.
If so, Go into disk management and right click the usb drive, click properties. Then assign it an unused drive letter.
Hope this helps
my usb will not recognize my mp3, or anything im running xp, any advice is appreciated

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