Frequent Pop-up, Traffic blocked from NTOSKRNL.EXE

Good day!  This has been a problem for some months, and I'm hoping someone can help me.  It's very annoying.  I've searched for solutions numerous times, but what I've found either didn't work or is too complicated for me to implement.

The pop-up is as follows:

Traffic has been blocked from this application:  NTOSKRNL.EXE

It appears about every 5 min all day, every day, and is starting to damage my sanity.

I'm using Symantec Endpoint Protection, version 12.1.2015.2015, managed by my company, and my computer is Win 7 SP1.

Any other information needed?

I am tech savvy but no expert, and I would very much appreciate any assistance!  Thank you kindly in advance!