Article ID: 2556113 - View products that this article applies to.
Consider the following scenario:
This issue occurs because the Autodiscover service uses the UserSite information to verify the Client Access server for OAB. However the UserSite information is set to the Mailbox server site. This behavior causes the Autodiscover service to refer the Outlook user to the Client Access server with the Mailbox server instead of the closest Client Access server.
To resolve this issue, install the following update rollup:
(https://support.microsoft.com/kb/2645995/ )Description of Update Rollup 1 for Exchange Server 2010 Service Pack 2
Note After you apply the update rollup, the Autodiscover service refers the Outlook user to the closest (local) Client Access server. However, if the user never retrieves a service connection point (SCP) object to the local Client Access server, or the local Client Access server does not have a copy of the user's OAB, the user downloads the OAB from the Client Access server in the same site where the Mailbox server is located. Additionally, the user can potentially download the OAB from a much farther site. Therefore, make sure that the appropriate SCP objects are set up, and that Active Directory sites are designated appropriately.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about the OAB, visit the following Microsoft website:
General information about the OABFor more information about how to download the OAB, visit the following Microsoft website:
General information about how to download the OABFor more information about the Autodiscover service, visit the following Microsoft website:
General information about the Autodiscover service
Article ID: 2556113 - Last Review: February 13, 2012 - Revision: 1.0