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When you use the OAuth protocol for authorization through Microsoft Exchange ActiveSync (EAS) in a Microsoft Exchange Server 2013 environment, the synchronization may sometimes fail.

Note This issue may also occur in an Exchange Server 2016 environment.


This issue occurs because the master security identifiers (SIDs) aren't handled correctly by the OAuth protocol. This causes the failure during the FolderSync process.


To fix this issue, install Cumulative Update 18 for Exchange Server 2013 or a later cumulative update for Exchange Server 2013.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

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