sudo fsck /dev/sdc
fsck from util-linux 2.27.1
e2fsck 1.42.13 (17-May-2015)
fsck.ext2: Attempt to read block from filesystem resulted in short read while trying to open /dev/sdc
Could this be a zero-length partition?

fdisk -l /dev/sdc
fdisk: cannot open /dev/sdc: Input/output error

sudo apt-get update
sudo apt-get install pmount