How to Register AJAX toolkit in web.config file in asp.net

How to Register AJAX toolkit in web.config  file in asp.net

Previously I was Explained about the Difference between Convert.tostring and .tostring() method Example ,  Reasons to use Twitter Bootstrap 

Re: Register AJAX toolkit in web.config file do the following steps 

1. Install the Ajax Control Toolkit as described in: http://www.asp.net/ajaxlibrary/act.ashx
2. Modify the web.config by adding the entries below.
 a. <add assembly="AjaxControlToolkit, Version=3.5.40412.0, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e"/>
                                Goes between <assemblies></assemblies> tag.
 b. <add tagPrefix="ajaxToolkit" namespace="AjaxControlToolkit" assembly="AjaxControlToolkit, Version=3.5.40412.0, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e"/>
                                Goes between <controls></controls> tag.

If you’ve installed some other version of the tool kit then make sure to replace a value of the Version attribute of both entries above.
To get the version just right click on the AjaxControlToolkit.dll and get the value of Assembly Version.

Here is what you’d need to use an ajax control on your page.
http://forums.asp.net/t/1255216.aspx
http://forums.asp.net/t/1262592.aspx