[.net] Microsoft.ReportViewer.Common Version=12.0.0.0

Issue

Parser Error Message: Could not load file or assembly 'Microsoft.ReportViewer.WebForms / Winforms, Version=12.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified.

Cause

Microsoft ReportViewer runtime and SQL CLR Types for SQL Server 2014 is required to run and is missing from the server hosting Internet Information Services (IIS) or your application.

Resolution

Install the following packages on the IIS server and then restart the system:

Download Microsoft ReportViewer runtime

Download Microsoft SQL CLR types for SQL Server 2014

Once restarted connect to Web service / Your app again and verify that the error has been resolved.

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