Web Debug

Fix broken web applications, from servers to clients.

Troubleshoot IIS crash issue

Debugging a .NET crash with rules in Debug Diag
By Tess Ferrandez

Even though debugging might be tricky, setting up rules in Debug Diag is beautifully simple and I personally believe that it would be a good idea for anyone running a web site to have debug diag installed along with a few instructions for the ops personnel on how to set up the rules. Better yet, you can set up the rules in advance and just activate or deactivate them as needed.

Problem description
The application crashes with the following event in the eventlog

Log Name: Application
Source: Application Error
Date: 2009-03-20 11:12:09
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer: MYMACHINE
Description:
Faulting application w3wp.exe, version 7.0.6001.18000, time stamp 0x47919413, faulting module kernel32.dll, version 6.0.6001.18000, time stamp 0x4791a76d, exception code 0xe053534f, fault offset 0x000442eb, process id 0x%9, application start time 0x%10.

ASP.NET 2.0 Crash case study: Unhandled exceptions
By Tess Ferrandez

Problem description
Once in a while ASP.NET crashes and we see events in the system event log like this one

Event Type: Warning
Event Source: W3SVC
Event Category: None
Event ID: 1009
Date: 2006-04-25
Time: 09:41:22
PM User: N/A
Computer: SUBSPACE1
Description:
A process serving application pool 'ASP.NET V2.0' terminated unexpectedly. The process id was ‘1732’. The process exit code was ‘0xe0434f4d’.

Or this one

Event Type: Warning
Event Source: W3SVC
Event Category: None
Event ID: 1011
Date: 2006-04-25
Time: 09:41:22
User: N/A
Computer: SUBSPACE1
Description:
A process serving application pool 'ASP.NET V2.0' suffered a fatal communication error with the World Wide Web Publishing Service. The process id was '6256'. The data field contains the error number.

And in the application event log we get a pretty cryptic error message like this one

Event Type: Error
Event Source: .NET Runtime 2.0 Error Reporting
Event Category: None
Event ID: 5000
Date: 2006-04-25
Time: 09:41:20
User: N/A
Computer: SUBSPACE1
Description:
EventType clr20r3, P1 w3wp.exe, P2 6.0.3790.1830, P3 42435be1, P4 app_code.pn5mfdcr, P5 0.0.0.0, P6 444dcf44, P7 5, P8 5, P9 system.dividebyzeroexception, P10 NIL.

I assumed you understand the exception processing in CLR, but if you are not, please refer to the article below.

Unhandled Exception Processing In The CLR
By Gaurav Khanna

Contents
Managed Exception Handling
Thread Base and Unhandled Managed Exceptions
Unhandled Managed Exceptions on CLR-Created Threads
Unhandled Exceptions on Non-CLR-Created Threads
Unhandled Exception Processing
AppDomain.UnhandledException Event Notification
Future Concerns

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