Invisible TabContainer within Ajax SmartPart

Feb 12, 2010 at 4:25 PM

I am using the "Ajax Smartpart" trying to add a very simple user control containing a TabContainer with 2 TabPanels.
For some reason, the TabContainer and so the TabPanels are invisible and on top of that I get the following javascript error:

Message: SysArgumentUndefinedException: Value cannot be undefined.

Parameter name: type

Line: 2705
Char: 12
Code: 0

NOTE: I believe the AjaxControlToolkit is intact and is installed correctly because I can place "Editor" and "FileUpload' controls from the same toolkit just fine.
I am using AjaxControlToolkit Version: 3.0.31106.0 and the UserControl looks like this.

<ajaxToolkit:TabContainer ID="TabContainer1" runat="server" BackColor="Blue" Width="500px" Height="500px" ActiveTabIndex="1" Enabled="true" Visible="true">
    <ajaxToolkit:TabPanel runat="server" ID="Panel1" TabIndex="0" HeaderText="Panel1" Enabled="true" Visible="true">
        <asp:Label ID="Label2" runat="server" Text="Label"></asp:Label>
    <ajaxToolkit:TabPanel ID="Panel2" runat="server" TabIndex="1" HeaderText="Panel2" Enabled="true" Visible="true">
        <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>

Am I missing something? Can someone shed some light? Thanking you in advance.
Sep 12, 2012 at 1:43 PM


I had a similar problem, and I was able to fix the problem
It was a conflicting ajax version for .net 3.5, as we move the application from .net 2.0. In summary I had to change the scriptmanager to ToolkitScriptManager in the masterpage, and it fixed most of the issues