A while back, I tried installing OS X Snow Leopard on a USB Thumb Drive (64GB) in order to see whether it could run on a Mac with a broken HD. It worked, but was obviously incredibly slow (I didn't have an external hard drive to test with at the time).
Now I have the Mac fixed, but I'm having problems with the USB. It still has MacOS on it, but I want to erase it.
Here's what I tried on macOS High Sierra:
Disk Utility -> Select the drive (grayed out) -> Erase: Gives error "Cannot write to last block of device"
diskpart list disk select disk 1 clean Error: Request could not be completed because of an I/O error.
GParted -> Select my disk -> Delete MacOS X partition
Gives error: Error fsyncing/closing /dev/sdb: Input/output error
This might not be the right forum to ask about this, but I figured it was caused by OS X, so I put it on here. I anyone has a suggestion of a better forum to go to, please tell me.
Does anyone have any idea how I might fix the USB Drive?