Assume that you are using Microsoft SQL Server 2016 or 2017 Reporting Services (SSRS). When the SSRS data source uses msmdpump.dll to establish a connection, you may receive an exception that resembles the following:
“AdomdConnectionException: The connection is not open”
This issue is fixed in the following cumulative updates for SQL Server:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminologythat Microsoft uses to describe software updates.