Element 'AccordionPane' is not a known element

I was wondering if someone can help me on a problem I'm having with a new AJAX project.

I open VS and Create a new Web Site using the ASP .NET AJAX-Enabled Web Site template.

In default.aspx there is a form tag, then a ScriptManager tag, then a Div.

I drag an Accordion control inside the div and run it.  It runs fine so far.

Then, I drag an AccordionPane control inside the Accordion control and i get this error:
"Element 'AccordionPane' is not a known element. This can occur if there is a compilation error in the Web site."

That's all I did. Any ideas? I run the AjaxControlToolkit sample just fine.

 It doesn't happen only on Accordion controls.  Also, I'm using a fresh copy of AJAX Beta 2 but I had Atlas previously installed which I uninstalled first.  I have already tried a couple of solutions found in other forums regarding something similar but didn't work.



11/20/2006 2:40:10 PM
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I just installed AJAX on another computer that never had Atlas installed before and I get the exact same error.  If anyone has any ideas it would be greatly appreciated.


11/21/2006 1:57:29 PM

Hi Nick,

I think you need to use the <panes> tage like this:

<cc1:Accordion runat="server" ID="MyAccordion" SelectedIndex="3" HeaderCssClass="accordionHeader" ContentCssClass="accordionContent" FadeTransitions="True"

TransitionDuration="250" FramesPerSecond="40">




<cc1:AccordionPane ID="AccordionPane4" runat="server" ContentCssClass="" HeaderCssClass="">


let me know how it goes....




MCPD - Web Developer
11/21/2006 3:04:18 PM
Bebandit, you're right I just figured it out too!  I spent a lot of time on this and it was that simple. Thanks!
11/21/2006 3:07:00 PM
I had followed the video which didn't use <panes> because it was for the Atlas version by the way.
11/21/2006 3:11:52 PM

Hey Nick,

I banged my head a while, too. It gets very confusing with all the different versions. I've been just putting my cursor under the control and pressing the "<" tag and let intellisense show me what is available.

Good luck!


MCPD - Web Developer
11/21/2006 7:52:41 PM

Bebandit, good idea thanks.  I'll try that if I come up to a similar problem again.


11/22/2006 8:08:56 AM

Okay, I put <panes></panes> in and I build wen fine. However, when I switch to Design mode, I got this error on the control:

Erro Creating Control -  Accordin1
'Panes' could not be initialized. Details: 'Panes' could not be added to the collection. Details: Object does not match target type.

7/18/2007 4:27:27 PM

Any other ideas on this problem?

7/19/2007 12:37:15 PM

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