AjaxControlToolkit with Sharepoint

Prerequiests

You have to configure your sharepoint for .net 3.5 framework
See this post

Download and setup AjaxControlToolKit to Sharepoint
Download AjaxControlToolkit

1-) Add your web applications web.config file in safecontrols tag

<SafeControl Assembly=“AjaxControlToolkit, Version=3.0.30930.28736, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e“ Namespace=“AjaxControlToolkit“ TypeName=“*“ Safe=“True“ />

2-)Add fallowings into your web.config-> Pages->Compilation->Assemblies tag

<add assembly=“AjaxControlToolkit, Version=3.0.30930.28736, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e“ />

3-) Reset your iis server

Do not forget to add assembly to your web page

<%@ Assembly Name=”AjaxControlToolkit, Version=3.0.30930.28736, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e” %>