Report Viewer Configuration Error -The Report Viewer Web Control HTTP Handler has not been registered in the application's web.config file. Add

Hay que agregar   3 etiquetas:

1)
 <compilation debug="true" targetFramework="4.5.2">
      <buildProviders>
        <add extension=".rdlc" type="Microsoft.Reporting.RdlBuildProvider"/>

      </buildProviders>


2)    
      <assemblies>
        <add assembly="Microsoft.ReportViewer.WebForms, Version=12.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91"/>
        <add assembly="Microsoft.ReportViewer.Common, Version=12.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91"/>
        <add assembly="Microsoft.Build.Framework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
      </assemblies>



3)

  <system.webServer>
    <handlers>
      <add name="ReportViewerWebControlHandler" preCondition="integratedMode" verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=12.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" />
    </handlers>

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