Adding the Ajax Control Toolkit to a SharePoint project

Question

I am unable to get the List Search Extender from the Ajax Control Toolkit to work correctly. After inserting my WebPart to the page, I get the error: "Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies. The system cannot find the file specified."

I followed the installation instructions for Visual Studio 2010 as found here. I see the AjaxControlToolkit listed in the references section of my solution and I have registered the assembly as shown in my code below.

*EDIT: Additionally, the assembly shows up in the GAC and I added a screenshot of the assemblies in my project package and the corresponding safe control in the Web.config

<%@ Register TagPrefix="asp" Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit"%>

<asp:ListBox ID="VendorSelector" runat="server"></asp:ListBox>
<asp:ListSearchExtender id="LSE" runat="server"
  TargetControlID="VendorSelector"
  PromptText="Type to search"
  PromptCssClass="ListSearchExtenderPrompt"
  PromptPosition="Top"
  AutoResetTimeout="0"
  QueryPattern="Contains"
  IsSorted="true"/> 

Answer 1

I added the version and public key of the assembly in my Register statement. No more runtime errors.

Answer 2

It appears that the version of the AJAX toolkit you are using is incorrect. I had this issue and after downloading and installing the correct version for my target sharepoint installation, and it worked. Hope this helps.