"asp:updatepanel" is not a known element using Visual Web Developer 2008 Express  Edition

        <asp:ScriptManager runat="server" ID="ScriptManager1" EnablePartialRendering="true" />

        <asp:UpdatePanel ID="OuterPanel" UpdateMode="Conditional" runat="server">

        </asp:UpdatePanel>

Make sure you have Framework .NET 3.5 SP1 installed on your computer. 

http://www.discussweb.com/asp-asp-net-programming/5087-i-am-getting-element-updatepanel-not-known-element.html

http://forums.asp.net/p/1038012/1772299.aspx 

Well I don't know why happened. I had 3.5sp1 on both dev machine with vwd2008ee and the iis hosting server. I created a new website on my dev machine and copied the web.config file to the server and everything worked. IDK why this wasn't already included in the config but thank you for pointing out the the registration in the config file. 

Now if I could only get the AJAX Extensions and AJAX Control Toolkit to show in my toolbox. (See my other post, Currently under mod review, if you might know how to fix)

Thanks for the help.