Commented Issue: Error: AjaxControlToolkit requires ASP.NET Ajax 4.0 scripts. Ensure the correct version of the scripts are referenced. If you are using an ASP.NET ScriptManager, switch to the ToolkitScriptManager in AjaxControlToolkit.dll. [27267]

I've that error.

My page has

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

...
<asp:ToolkitScriptManager runat="server">
</asp:ToolkitScriptManager>
...
<asp:TextBox ID="ColorInsertTb" style="width:60px" runat="server" Text='' EnableViewState="false" />
<asp:ColorPickerExtender runat="server" ID="ColorInsertPickerExtender" TargetControlID="ColorInsertTb" SampleControlID="ColorInsertSample" />


--------
last package from nuget
VS2012, asp.net 4.5

what an hell: every time I try to start the toolkit on a new project I've a lot of this troubles....

Comments: Fixed. the last missing part to fix issue is to delete Microsoft.ScriptManager.MsAjax.dll from app's references this will work along with the other changes mentioned in Stephen Walther's Post http://stephenwalther.com/archive/2012/09/20/september-2012-release-of-the-ajax-control-toolkit.aspx