Eddie, please explain a bit more about your problem.
Is the OneCare icon in your system try green, yellow or red? If it is yellow or red, when you open OneCare, it should tell you what action you need to take to put it back to green/good status.
What can you not update and what did you try to do to correct it?
Why do you believe that your PC is at risk of getting a virus.
As Wenske noted, you can contact support if you need to. Follow the instructions in the link Wenske posted.
-steve