You can download the Microsoft Report Viewer 2015 Runtime (which includes version assemblies) directly from the official Microsoft Download Center Microsoft Report Viewer 2015 Review
Once you have downloaded the executable from the Microsoft Download Center: microsoft report viewer version 12.0.0.0 download
References & Further Reading:
Benefits of Using Microsoft Report Viewer Version 12.0.0.0 You can download the Microsoft Report Viewer 2015
Installation Difficulty: Version 12.0.0.0 components, such as Microsoft.ReportViewer.ProcessingObjectModel.dll, are part of the larger official installer and cannot be downloaded as standalone files. Install the matching Report Viewer tooling or SQL
Standalone redistributable – Search your MSDN subscription or Volume Licensing center for “Report Viewer 2015 Runtime”.
If you are a developer integrating this into a project, use these packages: Microsoft.ReportViewer.Runtime.Common Microsoft.ReportViewer.WebForms.v12 Microsoft.ReportViewer.WinForms.v12 2. Critical Prerequisites The runtime will often fail to install or run without the SQL Server System CLR Types Microsoft Support You must install the Microsoft System CLR Types for SQL Server 2014 .NET Framework 3.5 SP1 is enabled on the system. ⚠️ Lifecycle & Support Notice