high CPU utilization in task aspnet_wp.exe

I encountered high CPU utilization in task aspnet_wp.exe which nearly 100%. It cannot be stopped by Windows Services and also cannot be ended by Task Manager.

May I know or trace what causes this problem? It just happened once few weeks before.

Here are the configurations of my system/application:
a. Windows 2000 Server with SP4
b. .NET Framework (1.0) Service Pack 2
c. There are Console Application and ASP.NET application running in the same server and they are both developed and coded by MS Visual Studio .NET (2002)
d. Console applications are scheduled and running periodically in Windows Scheduler.