Could not load file or assembly 'AjaxControlToolkit' or one

Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.

Parser Error Message: Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies. The system cannot find the file specified.

Source Error:

Line 1:  <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Registration.aspx.cs" Inherits="Registration" %> Line 2:  <%@ Register Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit" tagPrefix="ajax" %> Line 3:   Line 4:

Source File: /cbm/Registration.aspx Line: 2

Assembly Load Trace: The following information can be helpful to determine why the assembly 'AjaxControlToolkit' could not be loaded.

WRN: Assembly binding logging is turned OFF. To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1. Note: There is some performance penalty associated with assembly bind failure logging. To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].