[[To receive notification of missed tasks
1. Open Scheduled Tasks.
2. On the Advanced menu, click Notify Me of Missed Tasks.
A check mark next to Notify Me of Missed Tasks indicates that the service is
turned on. You can click Notify Me of Missed Tasks again to clear the check
mark and turn off the service. ]]
To receive notification of missed tasks
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/agent_notify.mspx