SAP Knowledge Base Article - Public

1540597 - Compiler Error Message: BC30560: 'CrystalReportViewer' is ambiguous in the namespace 'CrystalDecisions.Web'


  • When compiling a VS2010 web application that uses the CRVS2010 viewer the following error is thrown:
Server Error in '/' Application.
Compilation Error 
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.
Compiler Error Message: BC30560: 'CrystalReportViewer' is ambiguous in the namespace 'CrystalDecisions.Web'.
Source Error:
Line 7:  </asp:Content>
Line 8:  <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
Line 9:      <CR:CrystalReportViewer ID="CrystalReportViewer1" runat="server"
Line 10:         AutoDataBind="true" />
Line 11:     <h2>


  • Visual Studio 2010
  • Visual Studio 2008
  • Crystal Reports Basic for Visual Studio 2008
  • Crystal Reports for Visual Studio 2010

Reproducing the Issue

  • Install VS 2008
  • Install VS 2010
  • Install CRVS2010
  • Create a new WEB project
  • Add a Crystal Reports Viewer to a form
  • Run, or compile the project


  • The incorrect Register tag is added to the .aspx form when adding the 13.0.2000.0 CrystalReportViewer
  • The 10.5.3700.0 assembly is referenced in the Register tag instead of 13.0.2000.0
  • The issue has been identified and logged under Problem Report ID ADAPT01506310.


  • Remove the following from the web.config:

<add assembly="CrystalDecisions.Shared, Version=10.5.3700.0, Culture=neutral, PublicKeyToken=692FBEA5521E1304"/>
<add assembly="CrystalDecisions.ReportSource, Version=10.5.3700.0, Culture=neutral, PublicKeyToken=692FBEA5521E1304"/>
<add assembly="CrystalDecisions.CrystalReports.Engine, Version=10.5.3700.0, Culture=neutral, PublicKeyToken=692FBEA5521E1304"/>

  • Open the form that has the CR viewer on it, go to the code behind and replace the following:

<%@ Register assembly="CrystalDecisions.Web, Version=10.5.3700.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" namespace="CrystalDecisions.Web"; tagprefix="CR" %>


<%@ Register assembly="CrystalDecisions.Web, Version=13.0.2000.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" namespace="CrystalDecisions.Web"; tagprefix="CR" %>

  • In the Properties of the project, select references and remove crystaldecisions.web of version 10.5.3700
  • In the Properties of the project, click the Add button and then the .NET tab and select crystaldecisions.web version 13.0.2000.0
  • Recompile


CRVS2010 CR2010 2010 CR4VS2010 CD4VS Error Creating Control runtime deploy , KBA , BI-DEV-NET-SDK , .NET SDK / COM SDK , Problem


SAP Crystal Reports, developer version for Microsoft Visual Studio