What can cause ASPNET AJAX page to revert to normal ASPX mode ? / UpdatePanel broken

Question

I am using VS 2008 with a very simple UpdatePanel scenario. But i cannot get UpdatePanel to work and cant seem to find out why

I have in fact reverted to a very simple example to validate it is not my code: http://ajax.net-tutorials.com/controls/updatepanel-control/

In this example I click on either button and both text links update.

I dont get any errors, the page just behaves like a normal ASPX page. What things do i need to check. I've been googling this for an hour and not found what I need.

Edit: Works in Visual Studio web server but not in IIS

Answer 1

If it's working locally, but not when deployed to a remote server, that usually indicates that you're using ASP.NET 2.0 and the ASP.NET AJAX extensions aren't installed on the remote server.

If it's a server you have administrative control over, you can download the installer here: http://www.microsoft.com/downloads/details.aspx?FamilyID=ca9d90fa-e8c9-42e3-aa19-08e2c027f5d6&displaylang=en

If it's a web host, tell them to get their act together.

Answer 2

Another option would be to check your web.config. You could for example create an new Ajax enabled ASP.NET website from Visual Studio. This will generate a correct web.config. Copy over all non-ajax sections from your existing web.config and you're set. This worked for me.

-Edoode