Diskpart fixes broken USB thumb drives

Ever used a thumbdrive for some funky stuff, like shipping a PS2 bootloader or a linux distro and afterwards your drive reports to only being a fraction of it's original size?

A simple format will often fix that, but this time i wasn't so lucky. Even in computer management it was impossible to format the unallocated space.

But there is another tool in the shed, and it's called diskpart.

Simply type diskpart in CMD to start it.
Then follow the procedure below to clean the master boot record on your device and replace it with a fresh new one.

Be aware that choosing the wrong disk in this dialog will ruin your day.
But once that is done you can go format the thumb drive like usual, and it's now back to it's full potential again.

Such space... wow!