You have a mailbox that is in a Microsoft Exchange Server 2010 environment.
You access the mailbox by using an Exchange ActiveSync (EAS) device, such as an iPhone.
You search for a name or an alias against a global address list (GAL) of your organization as an email recipient.
In this scenario, results take longer than expected to be received.
This issue occurs because the EAS device uses Lightweight Directory Access Protocol (LDAP) queries for an Ambiguous Name Resolution (ANR) search. Generally, LDAP queries are not optimal for an EAS device.
To resolve this issue, install Exchange Server 2010 Service Pack 3 (SP3) on the Exchange Server 2010 servers. For more information about Exchange Server 2010 SP3, click the following article number to view the article in the Microsoft Knowledge Base:
2808208 Description of Exchange Server 2010 Service Pack 3
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about ANR, go to the following Microsoft website:
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.