I bought a memory stick (4 GB) a while back. It seems now my memory stick doesn't work in any of my computers USB ports, but it does work on other computers. Does this mean there is something wrong with my computers USB ports? everything else plugged into them works fine.
(I also removed the memory sticks unsafely a couple times due to freezing etc)
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Have you tried different USB ports, such as the ones in the back? Sometimes the front ones don't provide enough power?
Also, try removing some devices. They may conflict (a friend's external hard drive doesn't cooperate with other USB drives that are plugged in).
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