This Warning event occurs if the offline address book (OAB) version 4 manifest file cannot be loaded by OABGen.dll. The Microsoft Exchange System Attendant is responsible for invoking OABGen.dll so that address lists can be built or rebuilt. OABGen.dll is a MAPI application that reads from Active Directory through Name Service Provider Interface (NSPI) calls.

There is as yet no supplementary user action content specifically written to help resolve this Exchange 2010 Management Pack alert. Your attempt to get user action content for this alert helps us prioritize the Exchange Server 2010 Management Pack alerts for which we will be providing detailed User Actions. Here are some recommended next steps to learn more about this alert:

• Review the Application log and System log on your computers running Exchange 2010 for related events. For example, events that occur immediately before and after this alert provide more information about the root cause of this error.
  
  
• Research your issue by using self-support options. From the navigation pane of the Exchange Server Solutions Center page, click Self Support Options to use the following and other self-help options.
  
  
  • Search the Microsoft Knowledge Base. For example, search the Knowledge Base for key words in the Rule Name for this alert. If the alert was triggered by an event, search for the Event Source and event ID associated with this alert.
    
    
  • Visit and access the content available from the Exchange 2010 Forum Web site. You can also post a question at that Web site.
    
    
  • Visit and access the content available from the Exchange Server Community Web site.
    
    
• Research your issue by using other resources. From the navigation pane at the Exchange Server Solutions Center page, click Key Resources or other options to learn about other resources.
  
  
• Resolve your issue by using assisted support options. From the Exchange Server Solutions Center page, click Assisted Support Options to contact a Microsoft support professional. Your organization may have a specific procedure on directly contacting Microsoft Technical Support. Consider reviewing your organization's guidelines to get that information. If you do contact support, please have the event ID information available, and if possible, be prepared your application and/or system logs to be sent to Microsoft.
  
  

If you are not already doing so, consider running the Exchange tools created to help you analyze and troubleshoot your Exchange environment. These tools can help make sure that your configuration aligns with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. To run these tools, go to the Toolbox node of the Exchange Management Console. To learn more about these tools, see Managing Tools in the Toolbox.