screen saver issues and Norton Insight causes automatic shutdown/restart

Investigating screen saver problems here in the community, someone recommended clicking button by Norton Insight in the Tasks under Performance.  It seemed a wise choice since I noticed that NI has been showing "canceled" consistently (since the upgrade in Oct, I believe) - under the Ran During Idle whether "Yes" or "No."  After a few minutes running NI, the computer automatically shuts down and restarts.  I tried again and after running about 8 minutes, same thing - computer shuts down and restarts automatically.  Nothing registered on the NI line for these 2 attempts, it's showing the last record at 6:20 when it interrupted the screen saver last.

 

Thursday and Friday the computer shut down/restarted several times.  Sat., I ran the Full System Scan as it did not complete on 11/22 and had no problem with the shut down/restart since, until tonight - attempting to run NI.

 

Anyone else having this problem and is there a solution?  Thanks in advance.