Larry:

I certainly have seen a lot of people having system performance issues 
with NOD32, but this is the first application-specific error that I have 
heard reported.  Still NOD32 is doing a lot of background work on your 
system, so it is no hard to believe that this could happen.  Read on...

Larry Kost wrote:
> Greg
>
> A while back when we started converting to NODE32 we noticed so "odd" 
> behavior in Mathematica.  When you first tart it up, you get some sort 
> of Java link error.  
Well there is your problem right there... why would you want to tart-up 
Mathematica?  It is respectable software that does not need to be 
wrapped in garish clothing to make it attractive.
> This happens on both XP and Vista machines.  We contacted Wolfram and 
> suggested that it might have something to do with NODE32, but were 
> assured that it didn't.  They have offered no solution, so we started 
> things like disabling NODE32 and that seems to fix the problem, but 
> isn't a workable solution.  Since then I found an "Exceptions" setting 
> in NODE32 and added the Wolfram folder and that seems to do the job 
> also.  Is there a risk to doing this and do you have any other 
> suggestions.  
The risk of setting an exception is very minimal.  What you are doing is 
excluding Mathematica executables from threat scanning.  What are the 
chances that there will be an exploit written against Mathematica?

The only other thing I would try would be to verify your NOD32 
version...   currently we are distributing build 3.0.650.  Go to 
Help->About in the NOD32 console to see if you need to run an update.  
It has been my hope that between the build updates and the new less 
aggressive real-time scanner settings that most performance problems 
will disappear.
> We plan to get back to Wolfram now that we have "evidence" that NODE32 
> is the culprit.
>
Let me know what they say... I am expecting something like "Uh... maybe 
you should uninstall your antivirus software."

-Greg