PROBLEM
A user's Microsoft Exchange mailbox is migrated to Microsoft Office 365 from an on-premises or hosted Exchange environment. However, after the migration, the user's mobile device can't connect to Microsoft Exchange Online through Microsoft Exchange ActiveSync.
This occurs if the mobile device isn't automatically updated to include the location of the Exchange Online mailbox. The mobile device has to be redirected to the new mailbox server location.
This occurs if the mobile device isn't automatically updated to include the location of the Exchange Online mailbox. The mobile device has to be redirected to the new mailbox server location.
SOLUTION
To resolve this issue, use one of the following methods.
Install Cumulative Update 8 for Exchange Server 2013 or a later version. For more information about the latest updates for Exchange 2013, see Exchange Server Updates: build numbers and release dates.
For Exchange Server 2010 Service Pack 3 (SP3)
Install Update Rollup 9 for Exchange Server 2010 SP3 or a later version. For more information about the latest updates for Exchange 2010 SP3, see Exchange Server Updates: build numbers and release dates.
Method 1: Install Cumulative Update 8 for Exchange Server 2013 or Update Rollup 9 for Exchange Server 2010 SP3 or a later version
For Exchange Server 2013Install Cumulative Update 8 for Exchange Server 2013 or a later version. For more information about the latest updates for Exchange 2013, see Exchange Server Updates: build numbers and release dates.
For Exchange Server 2010 Service Pack 3 (SP3)
Install Update Rollup 9 for Exchange Server 2010 SP3 or a later version. For more information about the latest updates for Exchange 2010 SP3, see Exchange Server Updates: build numbers and release dates.
Method 2: Set up Exchange ActiveSync again on the mobile device
Set up Exchange ActiveSync again on the mobile device so that you can get the latest version of Exchange ActiveSync. To set up Exchange ActiveSync, go to Phone and tablet setup reference, and then follow the steps for your device.MORE INFORMATION
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