Errors and Warnings

This morning on two separate computer, my desktop and my wife's laptop, each time we sent an email through Outlook 2007, Norton's error menu popped up telling us the email was not sent because it is seen as spam.  The message tells us to contact http://www.charter.net/postmaster E5110.  I did. 

 

We are both using Windows 8.  I use Pro. Both 64.

 

The messages actually goes through.  Charter said there is nothing on their end which sees us as spam.  So, the problem seems to be with Norton.  How do I stop these messages from popping up on both machines when we send something????  It leaves us with the question, "Did it actually go through or do we need to try again?"