How long has it been since you upgraded your NonStop’s operating system? One year? Five years? Fifty years? You have no idea? Don’t feel embarrassed if you answered anything but “A.” You’re not alone. Many companies that operate within the NonStop environment have chosen not to upgrade their OS for a variety of reasons. Even though NonStop was designed to withstand the hardships of running continuously for years, it still needs to undergo routine OS upgrades just like any complex system.