I just installed RadControls for ASP.NET when I open my SharePoint site I get the following error:
Parser Error Message: Could not load file or assembly 'Telerik.Web.UI, Version=2008.1.512.20, Culture=neutral, PublicKeyToken=121fae78165ba3d4' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)