I was have this problem too, and when i was trying to load saves it was saying there stuff in the save that was no longer available, which i thought was ood since i didnt remember getting rid of anything that would cause that message, but i had been messin with stuff so i thought i may done something and just not remembered it. Then i remembered the last time i downloaded something recently NMM updated, so really not expecting anything i opened it up hit the plugin tab and low and behold none of the plugin were active