Double icons and double instances, please help!

I am using Norton Security Suite (the Comcast branded version that comes free with my cable subscription) on a computer running WIndows 7 64-bit.

Today, when I rebooted my computer, I noticed that I now have 2 Norton icons in my system tray instead of 1. I am very certain that up until yesterday I only had 1 icon in the system tray, and that this problem only happened after the reboot today. The reboot had nothing to do with Norton, it was related to a Windows Update.

I checked under Windows Task Manager and found that I have two separate instances of n360.exe running.

Here is a screenshot showing the processes and the duplicate icons:

 

 

Could someone explain how this happened and how to fix it? I don't want two system tray icons and I certainly don't want duplicate processes running.

Thanks!