When i upgrade ReportViewer from V11 to 15 Giving error
To easily upgrading from reportviewer version 11 to 15, you should consider to remove all old DLL of report viewer from your project and then you can install reportviewer version 15 using Nuget
Before installing above package also remove all reference of old Report viewer from Web.Config file.
Refer this article
To Have fresh installation of Reportviewer.
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