Windows 7: external hdd invisible to one of my 3 PC's ??

I have an external hdd that is not recognized by only one of my 3 PCs.
I have tried going through control panel>admin tools>computer mgt>storage>disk mgt
as well as hardware devices route and the PC still cannot see the HDD.



I have tried other ext hdd's with this PC and it sees them with no problem

Any ideas as to what the problem may be?? Thanks for your help

Just a guess. Is the external HD empty? Windows will not show empty drives unless you tick an option to do so.

thanks for your suggestion, but the disk has files, and operates normally on several other pcs.

Since the external drive works normally in other PCs, I would suggest that you try initialising it to the factory condition and start with a clean slate. I am hoping that this should resolve your problem.

1. Connect the external dive to the other PC in which it works and back up all the data in it to the internal drive ( if space is available) or to another external drive.

2. Download, install and run the HDD LLF Lowlevel format HDDGURU: HDD LLF Low Level Format Tool on it. ( Make sure that you remove all other external drives from the PC so that you make no mistake of running it on a wrong drive. )

3. Be patient and let the program complete writing zeros to each and every sector of the hard drive. This may take quite some time depending upon the capacity of the HDD.

4. After completion of the above step format your drive to the way you like.

Now try the drive on all PCs.

Note: You may also use diskpart - clean all Disk - Clean and Clean All with Diskpart Command to reinitialise the disk.

I would suggest that before installing the HDD Lowlevel Format Tool, create a System Restore point so that after completion you can remove the program by restoring the system to that point. That should do a clean removal. This is necessary since many have reported problems uninstalling it. I am assuming that Sytem restore works on that PC.

thank you very much for your help!
I followed all suggestions yet the external drive still will not show up on two of my pc's
All the pc's are Windows 7.
The 2.5" external drive works well only with my dell 14z laptop

Are all these PC's networked or do you unplug the HDD from each one and plug into another ? If so try changing the USB cable

thanks for your reply mitchell..the drive is being connected to each of the 3 pcs with usb cable.

Can you describe the 3 PC's you're talking about so we can see what might be different with the one that isn't showing your drive?

AGAIN:Have you tried a different cable? Have you given this Ext drive a dedicated drive letter? If so what's the letter? If so have the three other PC's got card readers fitted?
EDIT: I think the laptop came with Vista pre installed. Have you upgraded to Win 7? Where did the upgrade come from and are all the other PC's (How many are there BTW?) using the same copy of Windows 7?

Very peculiar. Have we gone from bad to worse? Earlier you said it was not recognised by one of the three PCs. Now you are saying it is not recognised by two of the three. The saving grace is it atleast works with one PC. I am scratching my head.

Is the drive still under store return policy?