External Hard Drive I O Device Error

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I / O error on the hard drive?

One day I woke up and turned on my computer, but when I tried to access my external hard drive, it just says "H: is not an application for access could not be achieved due to error I / O device. "How can I solve this problem? I prefer not to format, but if it's the only way to solve the problem. Drive is properly connected IDE is an external device connected via the USB port of my computer. I have tried in six on my computer.

First thing to check is this: Who is connected?! Sometimes, do not ask me how or why it is disconnected (i saw it twice). So try disconnecting and reconnecting. If you still have the error, it means that the hard drive is practically dead. He may want to load it as a slave and try access to them to save some data, but there is no guarantee it will work! I recommend not trying to "save" the file with a low-level format, because the disc later, and the data will be lost again. Better to try to salvage what they can now, using low-level see if a lot of existing damage, then there is too much to give. Good luck! PS: If it is a serial peripheral is attached, you may want to try install new sata drivers .......

NEW Hitachi Ultrastar 1TB 7200 RPM II hard disk drive    US $109.00

SMARTDISK 500GB USB 20 RJ 45 NDAS NAS HARD DRIVE    US $85.00

Seagate Barracuda XT ST32000641AS 2TB 35 SATA 2000GB    US $235.00