I have an external HDD that works on any other machine I test it on, except mine. It was working and for some reason I recently needed to use it and it didn't work. It appears in device manager but not in disk management. A drive letter might not be assigned to it, I can't see it in disk management to assign a drive letter to it.
Windows can get "confused" by all the old (and sometimes conflicting) USB storage driver data that tends to collect and remain installed on a PC.
Download drivecleanup.zip v0.8.1 from Drive Tools for Windows and extract it to a folder. You will find drivecleanup.exe, one for the 32bit Windows and one for 64bit Windows.
Unplug all USB devices in your system ( except the Mouse and Keyboard)
Right click on the appropriate one for your system and Run as Administrator.
This will remove all the non-present devices and all the corresponding registry entries left by them. You will now be starting with a clean slate.
Reboot your system and then plug-in your drive.
The necessary driver will be installed and your drive should be ready for use.
( I am not sure whether this will resolve your problem but there is absolutely no harm in trying it. I use this utility periodically to flush out the non-present devices and the driver references for these to avoid any problems.)
USB, I assume.
Does it show up in DiskPart?
If yes, then in diskpart,you can use the ASSIGN Letter=J
as an example which would assign the letter J to the currently selected volume.
WIN | type CMD | do NOT hit ENTER | CTRL + SHIFT + ENTER keycombo | ALT + Y keycombo
type following and hit Enter
DISKPART
type and hit ENTER
LIST VOLUME
from the list of volumes, find the one that corresponds to your external drive.
type and hit enter
SELECT VOLUME 8
here 8 is an example, you enter the correct volume number
type and hit enter
DETAIL VOLUME
this will reassure that you have the correct volume
type and hit enter
ASSIGN LETTER=K
here "k" is an example. Use the letter of your choice.
type and hit enter
EXIT
to exit the diskpart program
type and hit enter
EXIT to exit the command shell
None of those options worked. It is listed, no drive letter to read the content.
Just to confirm, this problem only happens on your computer? If so, and the drive works elsewhere, do other USB devices work on your computer?
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