String Date = "17/3/2015";
DateTime StartDate = Convert.ToDateTime(Date);
DateTime EndDate = StartDate.AddDays(7);

Console.WriteLine("Report Generated From {0} to {1}",StartDate,EndDate);



var Connection = from C in Sessions
where (C.StartDate >= StartDate && C.StartDate < EndDate && C.User != null)
select new {C.User.UserName,DG = C.Machine.DesktopGroup.Name};

//Console.WriteLine(Connection.ToList().GroupBy(u=>u.DG));
List<UserAndDG> UD = new List<UserAndDG>();
foreach(var user in  Connection.ToList().GroupBy(u=>u.DG).ToList() )
{
UD.Add(new UserAndDG(user.ToList()[0].DG,user.ToList().Count));
  
}
Console.WriteLine(UD.ToList());
}

public class UserAndDG
{
public string DeliveryGroup;
public int UserCount;
public UserAndDG(String DeliveryGroup,int UserCount){

this.DeliveryGroup = DeliveryGroup;
this.UserCount = UserCount;
	}