Low-level formatting is the process of outlining the positions of the
tracks and sectors on the hard disk, and writing the control structures
that define where the tracks and sectors are.

Flash disks simply don't have anything similar, nor do they have moving
heads which would need to be aligned.

I contacted SD support and they recommended that I use the disk manager under My Computer - Manage to format the drive using a card reader. For some reason I didnt think of this before. It took awhile but a format made the card readable. Thanks for the tip about checkdisk. I havent used that command in years.