I am getting System.PlatformNotSupportedException exception on running this code. can anyone tell me what is the problem in this code. public IList<ProductLine> GetProductLines() { //TODO Get Product Lines from SharePoint List<ProductLine> productlines = new List<ProductLine>(); SPSecurity.RunWithElevatedPrivileges(delegate() { using (SPSite configsite = new SPSite("http://<site>/")) { using (SPWeb web = configsite.OpenWeb()) { SPList list = web.GetList("Products"); SPQuery query = new SPQuery(); query.Query = "<OrderBy><FieldRef Name='Product Line'/>" + "</Order By><FieldRef Name='Product Line' />"; SPListItemCollection items = list.GetItems(query); if (items.Count > 0) { foreach (SPListItem item in items) { productlines.Add(new ProductLine() { Name = item.Name, Id= item.ID }); } } } } }); return productlines; }