Consider the following scenario:

  • You have a server that is running Microsoft Exchange Server 2010.

  • The name of a mailbox database on the server contains one or more of the following special characters:




  • You install Microsoft Exchange Server 2010 Service Pack 2 (SP2).

  • The System Attendant homeMDB attribute for a user points to the mailbox database that has special characters in the name.

  • The user tries to access the Exchange Server 2010 SP2 mailbox.

In this scenario, the MSExchangeServicesAppPool application pool crashes on the Exchange Server 2010 Client Access server (CAS). Therefore, Exchange Web Services (EWS) applications cannot connect to the servers that are running Exchange Server 2010.

Additionally, the following error message is logged in the Application log in Event Viewer on an Exchange Server 2010 Client Access server:

Log Name: Application
Source: MSExchange Common
Date: <Date>
Event ID: 4999
Task Category: General
Level: Error
Keywords: Classic
Watson report about to be sent for process id: <Process ID>, with parameters: E12, <Build Type>, <Version Number>, WS, M.Exchange.Diagnostics, M.E.D.RequestDetailsLoggerBase.SetBugdetSnapshotResourceInfo, System.IndexOutOfRangeException, <XXXX>, <Version Number>.
ErrorReportingEnabled: False

Log Name: Application
Source: ASP.NET 2.0.50727.0
Event ID: 1309
Task Category: Web Event
Level: Warning
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: <Date and Time>
Event time (UTC): <Date and Time>
Event ID: <ID>
Event sequence: <XX>
Event occurrence: <XX>
Event detail code: <XX>

Application information:
Trust level: Full
Application Virtual Path: /EWS
Application Path: <drive>:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\exchweb\EWS\
Machine name: <computer name>

Process information:
Process ID: <Process ID>
Process name: w3wp.exe

Exception information:
Exception type: IndexOutOfRangeException
Exception message: Index was outside the bounds of the array.

Request information:
Request URL: https://<ClientAccessServerFQDN>:443/EWS/Exchange.asmx
Request path: /EWS/Exchange.asmx
User host address: <IP>
User: <User>
Is authenticated: True
Authentication Type: NTLM
Thread account name: NT AUTHORITY\SYSTEM

Thread information:
Thread ID: <XX>
Thread account name: NT AUTHORITY\SYSTEM
Is impersonating: False

Stack trace: at Microsoft.Exchange.Diagnostics.RequestDetailsLoggerBase.SetBugdetSnapshotResourceInfo(String budgetResourcesString)
at Microsoft.Exchange.Diagnostics.RequestDetailsLoggerBase.FetchThrottlingData()
at Microsoft.Exchange.Diagnostics.RequestDetailsLoggerBase.Commit()
at Microsoft.Exchange.Services.Global.Application_EndRequest(Object sender, EventArgs e)
at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)


This issue occurs because the special characters in the database name cause an IndexOutOfRangeException exception. This exception crashes the MSExchangeServicesAppPool application pool.


Cumulative update information

To resolve this issue, install the following update rollup:

2645995Description of Update Rollup 1 for Exchange Server 2010 Service Pack 2

Hotfix information

An Interim Update (IU) is available from Microsoft. However, this IU is intended to correct only the problem that described in this article. Apply this IU only to systems that are experiencing the problem described in this article. This IU might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this IU.

To obtain this IU, contact Microsoft Customer Service and Support.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific IU. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft website:

More Information

This issue affects the following client applications:

  • Microsoft Outlook 2010 OOF and Availability

  • Microsoft Office Outlook 2007 OOF and Availability

  • Microsoft Outlook for Mac 2011

  • Microsoft Entourage 2008

  • Microsoft Office Communications Server

  • Microsoft Lync 2010

  • Unified Messaging

  • Mailbox Replication Service

  • Microsoft Office Outlook 2003 when it connects to RPC Client Access Service

  • Microsoft Project Server

  • Microsoft Outlook Web App

  • Blackberry Enterprise Server

  • Blackberry Internet Service

  • NitroDesk TouchDown with Microsoft Exchange ActiveSync

  • Apple Mail

  • Apple iCal

  • Apple Address Book


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

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