IIS Stops daily :((

There is something strange with one of my servers (win2k, IIS5).
The IIS stops once every 24 hours...
In the System Log :
"The IIS Admin Service terminated unexpectedly. It has done this n times etc....."
followed by:
"The World Wide Web Publishing service terminated unexpectedly. It has done this n times etc....."

In the Application Log - nothing interesting.

There are about 100 websites hosted at the server. Thanks God, the server is monitored and the downtime was only about a minute... but what could be the reason ? Any insights ? How to find out the source ?

10X in advance !

 

 

 

 

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