Error-could not find implementation of the query

Hi

  I am getting error - Could not find an implementation of the query pattern for source type 'Table'.  'SelectMany' not found.

var Result = (from t in context.View_SessionDeliveryCalendarDetails_Students
                                  from t2 in context.View_BookDetails
                                  where (int)t.BookID == (int)t2.ID
                                  && t.CurrentStatus == "Due" && t.SessionDate.Value.Date >= frDate && t.SessionDate.Value.Date <= toDate
                                  && (ddlDeliveryStatus.SelectedValue != "" ? t.BookDeliveryStatus == ddlDeliveryStatus.SelectedValue : 1 == 1)
                                  && t.BookID != 65 //&& t.SessionType == "Regular"
                                  orderby t.Name
                                  select new
                                  {
                                      t.GroupName,
                                      t.SessionDate,
                                      t.BookTitle,
                                      t2.AmazonName,
                                      t2.AmazonURL,
                                      TargetDelivery = Convert.ToDateTime(t.SessionDate).AddDays(-Convert.ToInt32(t.ReadngTime)),
                                      t.StudentID,
                                      GrpName = t.SessionType == "Regular" ? t.GroupName : t.LeadNumber
                                  }).ToList();
                    return Request.CreateResponse(HtpStatusCode.OK, Result, Configuration.Formatters.JsonFormatter);

Thanks