It looks like you downloaded the Q3 2008 version of the RadControl for ASP.NET (very different from the RadControls for ASP.NET AJAX). These are the old version of our controls (before we rebuilt the controls on top of the ASP.NET AJAX framework) and are updated to support customers still using them. The older controls are deployed in multiple assemblies and exist in the Telerik.Webcontrols namespace. The newer controls are all combined in one assembly (Telerik.Web.UI.dll) and all live inside the Telerik.Web.UI namespace. If you have been using the RadControls for ASP.NET AJAX
I highly suggest you head back to your Client.NET account and download the correct installation files. To download the RadControls for ASP.NET AJAX, navigate to http://www.telerik.com/account/purchases-and-downloads.aspx
(you must be logged in), click on 'RadControls for ASP.NET AJAX', and then select the 'Downloads' tab. You should see the latest version: Version 2008.3 1105
. Here is a screen shot
of what you should be looking at.
If you are an active subscriber and do not see the correct Q3 2008 version of the RadControls for ASP.NET AJAX in your account, open a ticket so that someone can help you out right away.