Strange Occurance with NIS

Last night out of the blue my NIS uninstalled it's self and rebooted my computer.. I ran malwarebytes and it found nothing, then I ran Norton eraser, and it found nothing that I did not know about and was safe. Then I ran NRnR and tried to reinstall. I have to do this several times before I finally got NIS to install and run, when i went to patch it to crapped out with the message it could not shut down the drivers and I needed to reboot to install the patch, I did this and everything was fine, it updated fine. I ran a quick scan and nothing. I am now in the process of running a full system scan but with 10TB of disk space it's taking a while.. Anyone got an idea what may have caused this? And could Norton be missing something?  Had IObit uninstaller and read that IObit products could cause issues so I removed that. I've never encountered anything like this before..  Thanks..