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: BC30007: Reference required to assembly 'Infragistics.WebUI.UltraWebTab.v5.1' containing the base class 'Infragistics.WebUI.UltraWebTab.UltraWebTab'. Add one to your project. Source Error: Line 12: </HEAD> Line 13: <body MS_POSITIONING="GridLayout"> Line 14: <form id="frmNATGAdministration" method="post" runat="server"> Line 15: <P align="center"> </P> Line 16: <P id="P1" align="center" runat="server"> Source File: http://localhost/FCE/NATGAdministration.aspx Line: 14Checking the references for the project Infragistics.WebUI.UltraWebTab.v5.1 is listed in the References node of the project.