Working external HD shows in Device Manager but not in Disk Management

I have read all the posts in this thread but nothing seems to work for me. I am running Vista Home Edition on a Fujitsu Amilo 2.33 GHz Quad core PC. I have 7 USB external hard drives that I connect to this PC from time to time without any problem. I also connect these drives to 2 other PCs (one of which is an identical Fujitsu Amilo PC) and 2 laptops. All drives are always recognised apart from one drive on one PC. This is an Iomega 320gb external hard drive, which shows under Device Manager as a Samsung320JX, but does not show in Disk Management or Windows Explorer. It has worked perfectly on this Fujitsu PC for over a year but now I cannot access it on this one PC, although It works on each of the other PCs and laptops. All my other external hard drives are recognised instantly on this PC whenever I plug them in (drive letters are assigned automatically) except for this one Iomega external hard drive. I have run the drive cleanup software recommended but this makes no difference. I have used different cables and different USB ports to try to get it to show on the Fujitsu (other than in Device Manager) but to no avail. Does anyone here have any insight as to how I might resolve this problem?

Sure sounds like a USB driver or filter issue. Have you tried these yet?
See [post=875300]How to Cleanup and Remove old USB Storage Drivers[/post]
See [post=815753]CD/DVD or Disk Problems? How to Fix Problems Caused by Filters[/post]

Thank you, you fixed my problem

Dear LookinAround
Thank you so much for your assistance - your step-by-step instructions on how to use Drivecleanup.exe worked perfectly and I can now access my Iomega external hard drive in Windows again! When I downloaded the software and ran it last night, prior to posting on this board, I read the accompanying text file but nowhere did it instruct me to place the file in the Windows/System32 folder, nor to run it under an elevated command prompt. I apologise for being such a noob and really appreciate your help in fixing this problem, which was driving me nuts.
What a great forum this is.

Hi Pachacuti

Thanks for updating us with the good news! And glad to help

The Remedy Works Short-Term

My inability to view USB hard drive contents was resolved by" "Rt click My Computer>Manage>Disk Management" shown on this thread. I did so by right clicking the unidentified USB drive that was shown in the Disk Management window and assigning it a unique drive letter. I assigned it "H" which left a gap between "E" and "G" for Win 7 to assign to other USB devices on a temporary basis. Unfortunately, this was only a temporary solution, as Win 7 does not retain it as a permanent assignment after dismounting that specific device.

Is there another way to permanently dedicate a drive letter assignment to a specific USB device, so that it will use the dedicated drive letter each time that it is mounted? My XP computer does retain dedicated drive letter assignments for USB devices that is repetitively mounted and dismounted.

@bobcinreno

Windows 7 should automount the USB drive just as XP does. If you can mount it manually, like you did, it may be a sign of a drive letter conflict. Did you also try removing old USB storage drivers? [post=875300]How to Cleanup and Remove old USB Storage Drivers[/post]

Corsair voyager 32gb usb 3.0

my USB which i have bought from amazon site stopped working and the format command of win xp sp3 gave me this message ( there is no device ) and HP USB Disk Storage Format Tool gave me no media in the specified device { the name has changed into Innostor NAND 1.00 (0 MB) what should I do I live in Jordan and the idea of returning it is little bit frustrating and cost a lot
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