The W3wp.exe process intermittently stops responding and Event ID 1000 is logged in Exchange Server 2007 Service Pack 1

On a server that is running Microsoft Exchange Server 2007 Service Pack 1 (SP1), the W3wp.exe process intermittently stops responding. Additionally, the following event is logged in the Application log:

Log Name: Application
Source: Application
Error Date: <Date Time>
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer: <Server Name>
Description: Faulting application w3wp.exe, version <version>, time stamp <xxxxxxxx>, faulting module exprox.dll, version <version>, time stamp <xxxxxxxx>, exception code 0xc0000005, fault offset <offset>, process id <xxxx>, application start time <xxxxxxxxxxxxxxxx>.

Note You cannot access the mailboxes when you use Outlook Web Access on a client computer.

To resolve this problem, install Update Rollup 5 for Exchange 2007 Service Pack 1.

For more information about Update Rollup 5 for Exchange 2007 Service Pack 1, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.