CPU 100%

Since installing Norton Anti Virus 2009 I have regularly had my screen freeze and the CPU usage indicate 100%. This never happen at all when I ran the 2007 version.

 

I have un installed Windows defender but do run NoAdware.

 

Does any one have any idea how I can cure this it is becoming extremely annoying and I do not want to have to change from Norton as it has done me well to date

 

Many thanks