This is a forum for feedback issues, and is not visited that often.
You would do better to post your problem in another forum. You haven't stated anything about your computer, eg what Operating System it has, so all I can suggest is to re-post in the Computer Help forum here;
http://forums.cnet.com/5204-6122_102-0.html?forumID=44&tag=dir.forum
or the Computer Newbies forum here;
http://forums.cnet.com/5204-6121_102-0.html?forumID=45&tag=dir.forum
A full list of forums is here;
http://forums.cnet.com/?tag=dir.forum
Mark
When i put my external hard disk (usb mass storage) running in my computer... why other usb device cant be detect ...unless i disconnected my external hard disk... my ext hard disk had a own power supply.

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