Hi @CC ,
Quote from the old thread missing Microsoft.SqlServer.ManagedDTS.
In the Add Reference dialog window, click on the browse tab. Then navigate your way to:
C:\Program Files\Microsoft SQL Server\90\SDK\Assemblies
There you will find the Microsoft.SQLServer.ManagedDTS.dll, select it and hit okay.
For Microsoft.SqlServer.Management.IntegrationServices, we can get this once we installed SSIS. Please check you have installed SSIS from SQL server configuration manager. Below is the test that I check today, once I add the SSIS feature in SQL 2019 instance in my environment, I get this file.
By the way, what is the version of your SQL server.
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