Hybrid Search: Inbound Query fails with 401

Last year I came across an issue where Inbound query was failing consistently. Issue applies to: April 2014 Cumulative Update or a later cumulative update forr SharePoint 2013 on-premises farm. When doing an Inbound Search ( i.e You search from SPO and expect to get results from SPO  and Onprem) you see the query fails…

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