Users cannot use eDiscovery on content crawled by SharePoint Server Cloud Search service
When you create an eDiscovery case, and you try to add a source for content that is crawled by the Microsoft SharePoint Cloud Search Service Application (SSA), you receive the following error message:
The connection to the search service application failed
To work around this problem, use the standard SSA to crawl items for the local index, and then query this index for your eDiscovery case. Both a standard SSA and the Cloud SSA can exist simultaneously as service applications on the server.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Article ID: 3160687 - Last Review: 06/22/2016 21:00:00 - Revision: 5.0
Microsoft SharePoint Server 2016