Microsoft.AspNet.ScriptManager.MSAjax 4.5.6 Microsoft Microsoft http://www.microsoft.com/web/webpi/eula/WebDeveloperTools_1_eula_ENU.htm https://download-codeplex.sec.s-msft.com/Download?ProjectName=aspnetwebstack&DownloadId=360555 true This package contains the Microsoft.ScriptManager.MSAjax assembly that will automatically register the Microsoft Ajax optimization bundle for Web Forms with ScriptManager.