SAP Knowledge Base Article - Public

1630689 - Error :"The type 'CrystalDecisions.Web.CrystalReportViewer' exists in both 'c:\WINNT\assembly\GAC_MSIL\CrystalDecisions.Web\12.0.2000.0_692fbea5521e1304\CrystalDecisions.Web.dll' and 'c:\WINNT\assembly\GAC\CrystalDecisions.Web\11.5.3300.0_692fbea5521e1304\CrystalDecisions.Web.dll'"


A custom  BusinessObjects Enterprise .NET web application to view a Crystal report, throws below error message.

  • "The type 'CrystalDecisions.Web.CrystalReportViewer' exists in both 'c:\WINNT\assembly\GAC_MSIL\CrystalDecisions.Web\12.0.2000.0_692fbea5521e1304\CrystalDecisions.Web.dll' and 'c:\WINNT\assembly\GAC\CrystalDecisions.Web\11.5.3300.0_692fbea5521e1304\CrystalDecisions.Web.dll'"
  • The application works fine on the development machine, but fails with the above error, when deployed on an IIS server.


  • Windows Server 2003
  • BusinessObjects Enterprise XI 3.1 .NET SDK



  • The application references the 12.0 version of 'CrystalDecisions.Web' dll.
  • The Default Web Site on IIS contains a Web.config file which contains references to the 11.5 version of 'CrystalDecisions.Web' dll.
  • When the application is run, conflict occurs between both Web.config files which results in the error message.


  •  Remove or rename the Web.config file from Default Web Site in IIS.

See Also

See KBase Article 1215784 - "Err Msg: 'CrystalDecisions.web.crystalreportviewer' is defined in multiple place" for information regarding a similar issue when using Crystal Reports 9.2 with Visual Studio.


multiple places, BOE.NET , KBA , BI-DEV-NET , BI Software Development Kits (SDKs) - .NET or Other , Problem


Crystal Reports 2008 V1