External USB drive doesn't show up any more

[jss2020]

I have a Seagate Backup Plus external USB drive that was working fine. I wanted to make it bootable so I tried to follow the instructions here:
http://www.youtube.com/watch?v=Jclt_ylFWXs

Unfortunately, my command prompt got stuck after the "clean" command and seemed it was never going to end so I manually closed the command prompt window. Next time I rebooted the computer I noticed that the external hard disk had stopped showing up in My Computers.

Is there any way I can get it back or does it seem damaged beyond repair?

I am using Windows 8.

Update: I see the drive mentioned under Disk drives in Device Manager only when I "show hidden devices".

Thanks!

JS

 

[jss2020]

Here how I solved it:

Go to Computer Management.
Select Disk Management under Storage.
The hidden drive will appear there.
Right click it and "change drive letter and paths".
Add a drive letter.

It will appear under My Computers.