Phantom LightningSand.CFD file

My system keeps getting disk errors on a file :

\Documents and Settings\All Users\Application

Data\Norton\{0C55C096-0F1D-4F28-AAA2-85EF591126E7}\Norton\SRTSP\LightningSand.CFD

(always the same index # 30)

I have no idea about where that file comes from. In fact, the file is

NOT there just before system shut down.... But it is still in error

before booting. It happens once or twice a week...

I now don't think the file has anything to do with Norton, but I do

not find any viruses with 5 different tools !!

Many messages on the web refer to that file as 'locked', which is kind

of normal as the directory where is goes is system locked.

Help !!