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.