I'd like to start a asp.net  project in Visual Studio 08 but the ajax templates are not there when I start a new website. In the toolbox the Ajax extensions are there but the items are disabled. I've read that the templates are included in 3.5. Can someone tell me how to install them in VS?

thanks

It depends on target framework version.

3.5: There is no AJAX Enabled Web site template, you can add Ajax Enabled Web Form to any Web site. Just create a regular Web site and add Ajax Web Form.

2.0: You need ASP.NET AJAX Extensions 1.0 which is a separate download. It also adds templates for 2.0 AJAX pages and sites.