This is the first I have heard of this, but Western Digital is NOT supporting relatively new drives on Windows 7. A member of our club switched and some of his drives don't work. He cannot even get his photos off the drives without finding another computer. I have two My Book Essential USB drives, both bought last year that are not compatible so I emailed WD. Here is my question and their answer.
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Are my My Book Essential drives (Model numbers WD5000H1U-00 and WD3200H1U-00) compatible with Windows 7?
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Thank you for contacting Western Digital Customer Service and Support. My name is Jose N.
Unfortunately the My Book Essential drive model number WD5000H1U-00 and WD3200H1U-00, are not comparable with Windows 7.
However, based on personal experience, if the drives are recognized by the computer with Windows 7 will work fine.
Unfortunately these drives are not support it by us on Windows 7.
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TF