NIS constantly saying At Risk

Hello,

 

My Norton internet security constantly says that it is at risk due to my virus & spyware definitions not being up to date. When I click fix now it just goes to download the latest updates, says I have them and then the fix now states that the fix is not complete. As a result of this, it is always red and I am now extremely hesitant to do anything on the computer as it may be completely messed up.

 

If anyone could please help me with this problem that would be great.

 

Cheers,