Endpoint Protection blocks internet activity every few minutes

I have Symantec Endpoint Protection version 11.0.6005.562 that I purchased through my University as a student.  For the last few months, I have continuously had the following issue: When accessing websites of all kinds, Symantec will periodically (every 5-10 minutes) I receive a notification like this or similar to it .  Followed by a notification saying "Denial of service logged."  After this, my internet connection is completely blocked for several minutes.  Since this happens every few minutes, it prevents me from getting anything done on the internet.  

Please advise as to the best way to deal with this issue.  Thank you.