Probably not possible to access the files on that corrupted drive. So you have to get them from your backup.
As we say here: "You only lose what you don't backup." Having only one copy of a file is an invitation for Murphy to come and visit you. That goes for internal and external hard disks, USB-sticks, sd-cards, and burned CD's and DVD's.
I have a Sandisk Ultra USB 3.0 32 GB flash drive. I have not had any problems with it until last night.
When I plugged it into my laptop (Windows 7) last night the USB did not show up under "Devices with Removable Storage". After some looking I found the flash drive listed under "Devices and Printers". I tried it on a desktop running Windows 10 and the same thing happened. Today I tried it on my work computer (Windows 7 Pro I believe) and the same thing happened.
The drive is not appearing in disk management so I am unable to try changing the drive letter. Is there anyway to fix this so I can access what is on the flash drive?