Hi Mark,
there are two seperate libraries:
The ASP.NET AJAX extensions which are available in VS 2008, and the ASP.NET AJAX Control Toolkit, which is not included but can be freely downloaded and referenced in any ASP.NET project. The ASP.NET AJAX extensions should provide the basic AJAX controls inside the toolbox (e.g. Timer, UpdatePanel)
Regards
Marco Buerckel
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