Have you tried to read the usb HD on another computer?  If so, what were 
the results?
Paul Hachmeyer

Brad Lindroth wrote:

>Larry,
>
>Just out of curiousity, what does the disk look like in "Computer
>Management">"Disk Management". Does you see it there? Is there a partition?
>Healthy? Formatted with NTFS or FAT? A little more info may help track this
>down.
>--
>Brad Lindroth
>Georgetown, South Carolina
>
>-----Original Message-----
>From: Personal Computer Hardware discussion List
>[mailto:[log in to unmask]] On Behalf Of Larry Scroggs
>Sent: Thursday, March 22, 2007 8:35 PM
>To: [log in to unmask]
>Subject: [PCBUILD] External USB HD not being recognized
>
>I submitted the message below over a week ago and never had a reply. Can
>anyone help me out? Thanks.
>
>I am using a system I built about a year and a half ago and up until the
>last two weeks I have had no problems with it.
>System specs are:
>Windows XP Professional Service Pack 2 (build 2600) with all updates,
>2.40 gigahertz AMD Athlon 64,
>A: drive 3.5" format removable media [Floppy drive],
>C: drive Maxtor 6B300S0 [SATA Hard drive] (300.08 GB) -- drive 0,
>D: drive PLEXTOR DVDR PX-716AL [CD-ROM drive],
>E: drive PLEXTOR DVDR PX-740A [CD-ROM drive],
>K: drive WDC WD25 00JB-00GVA0 USB Device [Hard drive] (250.06 GB) -- drive 2
>HP psc 2175xi USB Device [Inkjet scanner/printer] -- drive 1,
>Motherboard MICRO-STAR INTERNATIONAL CO., LTD MS-7100 1.0
>2GB RAM
>
>The USB HD is used for backing up my internal HD. I have used it weekly
>since building the machine. Lately it no longer shows up in "My Computer".
>If I look in "Device Manager" the USB WD HD is recognized under "Disk
>Drives" as USB Device - drive "K" along with the Maxtor SATA HD as drive "C"
>and the HP psc 2175xi as USB Device without a drive letter designation.
>"Device Manager" show the USB HD as working properly. I have disabled and
>reenabled it. I have tried uninstalling it and having Windows XP redetect
>it, all to no avail. I have tried the drive on several different USB ports
>on my machine with no joy. 
>
>I will appreciate any help you can offer. Thanks.
>
>Larry
>
>Larry Scroggs
>[log in to unmask]
>El Paso, Texas, USA
>
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