Did you go into the Disk Configuration Manager (diskmgmt.msc) and assign
drive letters to the partitions on the drive? Ignore any message(s) to
format the drives, simply assign letters and all should be well.

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Richard G. Harper [MVP Shell/User] rgharper@gmail.com
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>I have a portable harddisk using USB 2 interface, when i boot into
>microsoft
> vista i can see the device, but unable to read the paritions under it, but
> when i boot under windows XP SP2, the USB portable harddisk works as fine,
> is
> it a bug in this vista build?