This Error event indicates that DSProxy.dll is missing or could not be found. If DSProxy.dll cannot be found, the Microsoft® Exchange System Attendant service may not start.

To resolve this error, follow these steps:

• Make sure that DSProxy.dll exists on the server that is running Microsoft Exchange Server that logged this event. To do this, follow the steps given here:
  
  • Open Microsoft Windows® Explorer.
    
  • Locate C:\Program Files\Microsoft\Exchange Server\Bin and confirm that DSProxy.dll exists.
    Note   If you specified a different install location when you installed this Exchange server, open the Bin directory of that location.
    
• Confirm that the HKEY_LOCAL_MACHINE\Microsoft\Exchange\Setup registry key has the required permissions. To do this, follow the steps given here:
  Caution    Incorrectly editing the registry can cause serious problems that may require you to reinstall your operating system. Problems resulting from editing the registry incorrectly may not be able to be resolved. Before editing the registry, back up any valuable data. 
  
  • Start Registry Editor (regedit).
    
  • Locate the following registry key: HKLM\SOFTWARE\Microsoft\Exchange\Setup, right-click the registry key, and then select Permissions.
    
  • Click Advanced.
    
  • Make sure that the Allow inheritable permissions from the parent to propagate to this object and all child objects option is selected.
    
  • Use the following matrix to verify that the HKLM\SOFTWARE\Microsoft\Exchange\Setup registry key has the required permissions:
    

    Administrator, Domain Admins, Enterprise Admins, Exchange Organization Administrators and System	Full Control and Read access
    <MachineName>$, Exchange Domain Servers, Exchange Servers, Exchange View-Only Administrators and Users	Read access
    Creator Owner	Special Permissions
    Power Users and Terminal Server User	Read and Special Permissions

• Make sure that the Services REG_SZ registry entry under the HKLM\SOFTWARE\Microsoft\Exchange\Setup registry key has the correct path of the DSProxy.dll file. To do this, follow these steps:
  
  • Start Registry Editor.
    
  • Locate the following registry key: HKLM\SOFTWARE\Microsoft\Exchange\Setup and double-click the Services registry entry in the results pane.
    
  • Make sure that the Value data contains the following value: C:\Program Files\Microsoft\Exchange Server.
    Note   If you installed this Exchange server in a different location, make sure that the Value data contains that location.
    

To search the Microsoft Knowledge Base articles based on criteria that generated this alert, visit the Search the Support Knowledge Base (KB) Web site.

To review Exchange 2007 event message articles that may not be represented by Exchange 2007 MOM alerts, see the Events and Errors Message Center.

Note  If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.