Your comments lead me to agree, 1st a power down reset, AFTER you replace the software battery, located on the right side of the card cage.
The battery is a CR2032, don't drive the clerk crazy. It seems to be available many places for many uses. I've even seen it at Wal-Mart! Apparently, it fits some watches. But look at the battery before you go out to buy 1. The very early software packs used a different configuration that 'stands' on 3 legs, while the CR2032 is the proverbial 'coin' battery. The '3-legged one' can be tough to find. Like Dane said, Good Luck.
John C. (Not Garand)