Problem with Task Scheduler Service

Hi,

I have a trouble with Win XP Home (SP2) :-)

If I use Task Sheduler Service, my pc crash with error 0x000000F4

between 15-20 minutes with no activity.

I suspect at this time my pc run into Idle time and process a

task... and this task crash my session.

I search what is the name of process (or task, or .exe or .dll).

If I not enable Task Sheduler Service, I have no problem.

Or if I work with my pc, I have no problem.

My problem appear only if I not use my pc.

My Disply Properties "Screen saver" is [none], "Background" is

Bliss.