I am testing AJAX.  I've downloaded the AJAX Extension and the CTP December package and installed on BOTH my development machine and the production server. 

Then I created a very very simple web application, which contains a button and a label.  When the button is clicked, some message is shown on the label.  That's it.

 The AJAX works great on my development machine, but on the production server, I got the typical error as follows: 

Server Error in '/' Application.

---

Configuration Error

Description:An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.

Parser Error Message: Could not load file or assembly 'System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.

Source Error:

Line 36:     <compilation debug="false">
Line 37:       <assemblies>Line 38:         <add assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>Line 39:       </assemblies>
Line 40:     </compilation>

I searched this forum, one guy mentioned that Microsoft.Web.Extensions.dll and Microsoft.Web.Extensions.Design.dll need to stay in the bin folder of the application.  I don't think this is true any more.  That said, I still tried it, with no luck on the production server.

Could you please help diagnose what might be wrong with the production server side?  Thanks.