You try to perform an eDiscovery search in the Exchange Admin Center (EAC) in an Exchange Server 2013 environment by using the following conditions:
The source mailbox is in an on-premises Exchange environment.
The on-premises Exchange environment has a cloud archive.
In this situation, the search finishes and you receive the following error message:
Failed Search or Export, Mailbox:/o=Contoso/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=user::Item:::DocumentId:::ItemId: with error: [FailedToSearchMailboxes] Class ExtendedAttribute is only valid for Exchange version 1941996250 or later.
This problem occurs when Autodiscover sends information that the Exchange Server 2013 eDiscovery function cannot handle well.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology that Microsoft uses to describe software updates.