I developed a application site where one facility is FAQ in which user can post text data without any limit. I hv two server to run the application whenever a single field (question or answer) size is huge (like one page long) one of the server is giving service unavailable. I checked in log the error detail is
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Event Type: Error
Event Source: W3SVC
Event Category: None
Event ID: 1002
Date: 1/23/2012
Time: 3:29:49 PM
User: N/A
Computer: BA5SWWW006
Description:
Application pool 'pool_name' is being automatically disabled due to a series of failures in the process(es) serving that application pool.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
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AND ALSO
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Event Type: Error
Event Source: VsJITDebugger
Event Category: None
Event ID: 4096
Date: 1/23/2012
Time: 3:29:44 PM
User: NT AUTHORITY\NETWORK SERVICE
Computer: BA5SWWW006
Description:
An unhandled win32 exception occurred in w3wp.exe [10896]. Just-In-Time debugging this exception failed with the following error: Debugger could not be started because no user is logged on.
Check the documentation index for 'Just-in-time debugging, errors' for more information.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 02 00 5c 80 ..\
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but the other server is working fine. i check all d basic setting of both is same. and also there no such logged in error for any other module. Even error wont occur for same module if the text in question or answer is less.
when this occur it ask for enter the user credentials i couldn't understand why it prompt for such?????
i use my-sql with longtext field to store question or answer.
May be best to try the IIS Debug Diagnostics Tool to further diagnose the problem.
This SO question has plenty of other suggestions: How to diagnose IIS fatal communication error problem