This just started happening again, with these errors appearing in the event viewer:
Log Name: System Source: Microsoft-Windows-WAS Date: 9/18/2011 11:16:33 AM Event ID: 5011 Task Category: None Level: Warning Keywords: Classic User: N/A Computer: exch2010fe1 Description: A process serving application pool 'MSExchangeOWAAppPool' suffered a fatal communication error with the Windows Process Activation Service. The process id was '3760'. The data field contains the error number. Log Name: System Source: Microsoft-Windows-WAS Date: 9/17/2011 6:47:07 AM Event ID: 5009 Task Category: None Level: Warning Keywords: Classic User: N/A Computer: exch2010fe1 Description: A process serving application pool 'MSExchangeOWAAppPool' terminated unexpectedly. The process id was '3108'. The process exit code was '0x800703e9'. Log Name: Application Source: Application Error Date: 9/17/2011 6:46:30 AM Event ID: 1000 Task Category: (100) Level: Error Keywords: Classic User: N/A Computer: exch2010fe1 Description: Faulting application name: w3wp.exe, version: 7.5.7600.16385, time stamp: 0x4a5bd0eb Faulting module name: KERNELBASE.dll, version: 6.1.7600.16385, time stamp: 0x4a5bdfe0 Exception code: 0xe053534f Fault offset: 0x000000000000aa7d Faulting process id: 0x%9 Faulting application start time: 0x%10 Faulting application path: %11 Faulting module path: %12 Report Id: %13
After reviewing the IIS logs and the event logs, I think it has to do with the WebReady document viewer – the thing in OWA that renders and lets you view .doc attachments within the browser rather than forcing you to open Word or Excel. I think users were attempting to open corrupted files and that was causing it to crash. I’ve disabled Webready in EMC (Server Config -> CAS) and I’ll see what happens.
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This happened again this past Saturday, so apparently it doesn’t have anything to do with WebReady documents, since that’s disabled. Looking in the IIS logs, there was a user logged in with Safari on Mac OS 10.6.8 at the time of the crash. I talked to the user and he said he was just going through his emails and at some point the UI became unresponsive. When he reloaded the page, he got the 503 error. When this happened 3 weeks ago, the same user was logged in. That’s pretty strange.
Just started getting this issue yesterday evening and i’m only managing to get by by running an iireset command every hour or so. System’s been in place for 18+ months and this just now has started.
Check your Event Logs & IIS logs and see if you can cross reference the time of the “appcrash” event with a particular request in IIS. I’m curious if it’s some particular browser quirk (in my case it seemed to be Safari on Mac that triggered the error twice).
Just did (thanks for the quick response) I noticed the latest crash (3:56 PM EST) a user with a Mac was logged in using the Mac version of Outlook (I think, maybe it was Entourage).
Had him log in again but did not replicate (i did this over the phone so can’t be 100% since it was a remote user)