First thing is to try accessing it from another computer.
Try from both PCs and Macs. If you also have access to one using Linux, try that also.
If after trying on several computer ans OS you still can't access it's data, it have devloped some fatal fault and need, at least, to be reformated.
In this case, ANY data it may contains is ALREADY lost.
Electro
April 2011
If you have important data, the answer is to make more than one copy of it. Don't rely on your pendrive, as you have found to your cost, they are not 100% reliable, nothing is.
DB
March 2011
Automatic Answer
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