ccSvcHst loops when Norton Insight scan runs

I have been having a problem for a few months.  Every time an Insight scan runs, a ccSvcHst process ends up looping.   Norton Antivirus says that it is using 100% of the CPU.  No matter what I do, I cannot stop the loop (can't terminate the process, can't do anything in Norton Antivirus to stop it) and the computer is essentially unusable.  It may come out of it eventually, but I have seen it go for more than an hour.  The only way to get out of it is to reboot.

 

It appears that the Insight Scan completes eventually (if I don't reboot), but the loop never ends.

 

The system is Windows XP Professional, SP3

 

In addition, if I try to contact Norton through the "1-click" help, then HSLoader loops in the same way.

 

Does anyone know what might be wrong here, and how I can avoid this problem?

 

Mike