IIS 6.0 Application Pool crash


Have a lot of troubles on production server. Some routing cause crashing of Application Pool with event id 1011:

Event Type: Warning
Event Source: W3SVC
Event Category: None
Event ID: 1011
Date: 1/21/2009
Time: 9:08:17 AM
User: N/A
Computer: xxxxxxxxxxxxx

A process serving application pool 'DefaultAppPool' suffered a fatal communication error with the World Wide Web Publishing Service. The process id was '3788'. The data field contains the error number.

I have a few very hard hours for me before I found a problem.
Thanks to Tess Ferrandez and her blog post I found it.

Always double check Your multithreaded code in asp.net application. When Unhandled exceptions occurs application pool crashes and it's damn hard to find WHY.

Best Solution

Tess's blog was a little advanced for me. I had to search around for quite a bit before I found the right articles that helped me debug my dump files. This article will help others who want to debug their crashing asp.net application pools but don't know how to start.