1. A method comprising: programming memory cells in a memory block of a memory array above a pre-determined level, the memory array being separated into memory blocks including the memory block, each of the memory blocks having a plurality of memory cells, each memory cell being a multiple level memory cell; applying an erase pulse to the memory block; after applying the erase pulse, verifying each memory cell of the memory block to determine if all the memory cells in the memory block are in an erased state; and checking to determine if there is an over-erased memory cell in the memory block.