External USB drives using letter E: not showing in "My Computer"

When I plug any hard drive or memory stick into either USB port on my Dell XP computer, the default E: drive letter and device does not appear in the "My Computer" window. I can see it when I access the administrative tool for storage devices and access it there also.

If I change the drive letter to any other letter, all works fine and the drive is forever denoted with whatever drive letter I have assigned. The problem is that the E: is always the default and therefore any new device requires a manual letter assignment in order to make it operate.

I think the problem began when I was downloading a large set of files from a friend's external hard drive. It all went okay until one of the files hung up the system due to some sort of fault in the file. I waited a long time for the computer to resolve the problem but nothing happened. Instead of trying the Task Manager to stop the process, I forced a shutdown with the on/off button.

I have tried uninstalling the USB driver and also uninstalling various drives. All the drives work fine in my other computers. My friend's drive worked okay after I re-booted, and I was able to complete the upload. The problem seemed to start after I got a blue screen when performing another boot-up the next day. I shut down from the blue screen (it just said there was a serious error without defining it) and restarted normally and all - except the drive letter issue - worked fine.

I would appreciate any assistance.

Hi Toucan,

Welcome to Seven Forums.

OK, it looks like some program you had installed had disabled the automount and always looks for and assigns a drive letter to the pen drive. (my guess). This in most cases can be corrected by entering into the program settings and making the necessary changes.

Can you recollect any such program that looks for a drive?

What programs/games did you install recently?

What are those "large set of files" you downloaded?

Hi Jumanji,

Thanks for the reply.

I have not installed any programs recently. I have only been uploading and downloading lots of music and book files as part of backing up my data. Uploading music was the last one used before the problem occurred. The hard drive that I was reading from did not have any programs on it. I haven't loaded any new programs or games for a very long time.

OK, then we are going to shoot in the dark.:) ( If it misses the target the bullet just flies off into oblivion without doing any harm, so no worries.)

Pull out all USB drives and do a drive cleanup . My post #2 here USB Thumb Drives not recognised (not drive letter)

After the drive cleanup, reboot.

Go to Start > All Programs > Accessories Right click on the Command Prompt and Run as administrator

as in the screenshot enable automount .



diskpart [Enter]

automount enable [Enter]

exit [Enter]

exit [Enter]

Now plug in your pendrives and check.

Let us know whether the problem is resolved.

Will do. It'll be a day before I get back to you as the problem is with the computer that I don't have with me right now - and I will definitely let you know what happens.

Thanks again...

I followed your suggestion today and it made no difference. I ran some other checks and found that if I have a device plugged into a USB port that defaults to E: and doesn't show, then plug another device into the other USB port (I have only two), the second device is recognized as F: and all is fine with that device. If I unplug both devices then plug the second one in again by itself, Windows picks it up still as F:. That tells me that it permanently assigned F: to that device. If I plug the wireless mouse into the USB 2 port, which is what I usually do, then an external hard drive or memory stick into the SS USB port, the problem remains the same. However, if I plug the mouse into the SS port and then a device into the regular speed port, the computer won't recognize it at all and the storage manager part of computer management locks up. Maybe this extra info will help you?

Sorry Toucan, I am unable to visualise this peculiar problem. Let us see whether others could help you in this.

I shall continue my digging on this problem and will return if I could get any clue on it.

Check whether Microsoft Fix-it fixes it. See 3. here USB Drives not detected

I found a Microsoft forum where someone with the identical problem was advised of a fix. I tried that fix (uninstalling all the USB ports - which I think is what the drivecleanup did? - then downloading and running Intel Matrix Storage Manager. The computer would not run the program, showing a notice that my computer was not able to run it. So I guess I'm still stuck. Right now I am going to go back to see if there is anything else from Microsoft.

Thank you for your efforts. If I find a fix, I will post it here.

You should perhaps let us know your motherboard details.

If you have a USB to PS2 connector or a PS2 mouse try it instead of the USB mouse. ( After such a mouse is connected run drive cleanup after removing all USB devices so that all non-present devices and their registry entries are cleared.)

Also please give the reference to the MS thread you found.

The machine processor is Intel Core 2.8 ghz, I7-2640M CPU 2.8 ghz. Ram is 8 gbytes. 64 - bit operating system. It's running Windows Home Premium Service Pack 1. Is this what you wanted?

I don't have any non-USB wireless mice. When I ran drive cleanup, I had already unplugged the mouse and left it unplugged while using the touchpad instead.

The forum was called Windows 7 IT Pro Forum and it referred to this site:
Windows 7 x64 Quit Assigning Drive Letters Automatically... ??

I am going to head back there now and poke around to see if I can learn some more...