Config to stop Firefox interference?

Norton Security | Norton Internet Security
1

I suspect Norton Antivirus may be interfering with Firefox and it's addons. I wonder how I might better configure Norton Antivirus 21.5.0.19 to let Firefox and it's addons function properly, please?

 

The problems relate to updating Firefox 31 and most of it's addons. Just for one example when an addon tries to save data.

 

I've explored ALL options implicating Firefox 31 and the addons, including of course un/re-installs. It's a fresh install of Win7Pro32-bit (my first post-XP system).