New install of Umbraco 4.0.1 and everything seemed to be going fine until I tried to launch the admin.

Getting the following error: Method not found: 'Void System.Web.UI.ScriptManager.RegisterClientScriptBlock(System.Web.UI.Page, System.Type, System.String, System.String, Boolean)'.

[MissingMethodException: Method not found: 'Void System.Web.UI.ScriptManager.RegisterClientScriptBlock(System.Web.UI.Page, System.Type, System.String, System.String, Boolean)'.]
umbraco.cms.presentation.umbraco.PageLoad(Object sender, EventArgs e) +0
System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
System.Web.UI.Control.OnLoad(EventArgs e) +99
umbraco.BasePages.BasePage.OnLoad(EventArgs e) +15
System.Web.UI.Control.LoadRecursive() +50
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627


I looked through the forum and found only one reference to this, that had to do with ASP.net AJAX 1.0 being installed. I have verified that it is installed but still can't get it to work.

Any thoughts or suggestions would be appreciated.