I got this error with the following control in asp.net 4.0.  Any idea how to fix it?  Thanks.

The base class includes the field 'WebDataGrid1', but its type (Infragistics.Web.UI.GridControls.WebDataGrid) is not compatible with the type of control (Infragistics.Web.UI.GridControls.WebDataGrid).

<ig:WebDataGrid ID="WebDataGrid1" runat="server" Width="100%" Font-Size="X-Small" AutoGenerateColumns="False" DataKeyFields="ID" EnableDataViewState="True" DefaultColumnWidth="80px">

  <Behaviors>

    <ig:Activation Enabled="true" />

    <ig:Selection RowSelectType="Multiple" CellClickAction="Cell" />

    <ig:EditingCore AutoCRUD="false">

    <Behaviors>

       <ig:CellEditing EditCellCssClass="Right">

         <EditModeActions EnableF2="true" EnableOnActive="true" MouseClick="Single" />

      <ColumnSettings>

         <ig:EditingColumnSetting ColumnKey="ID" ReadOnly="true" />

         <ig:EditingColumnSetting ColumnKey="NumOfBranch" ReadOnly="true" />

         <ig:EditingColumnSetting ColumnKey="Total" ReadOnly="true" />

      </ColumnSettings>

      </ig:CellEditing>

    </Behaviors>

    </ig:EditingCore>

    <ig:ColumnFixing ShowLeftSeparator="true" ShowRightSeparator="true" AutoAdjustCells="true">

       <PinButton HoverImageUrl="~/images/icunpinned.GIF"            

ImageUrl="~/images/icunpinned.GIF"

                            PressedImageUrl="~/images/ICPINNED.GIF" />

       <UnpinButton HoverImageUrl="~/images/ICPINNED.GIF"

                            ImageUrl="~/images/ICPINNED.GIF"

                            PressedImageUrl="~/images/icunpinned.GIF" />

   <ColumnFixingClientEvents FixedStateChanged="WebDataGrid_FixedStateChanged" />

  </ig:ColumnFixing>

  </Behaviors>

  <EditorProviders>

    <ig:WebTextEditProvider ID="WebTextEditProvider10" />

  </EditorProviders>

</ig:WebDataGrid>