expects parameter '@ID', which was not supplied?

Question

I am sending ID as outparameter but its giving error

System.Data.SqlClient.SqlException: Procedure or function 'usp_ClientHistoryItem' expects parameter '@ID', which was not supplied.

Code

 using (SqlCommand cmd = new SqlCommand("dbo.usp_ClientHistoryItem", conn))
 {
      SqlParameter parameterID = new SqlParameter("@ID", oReservation.Id);
      parameterID.Direction = ParameterDirection.Output;
      cmd.Parameters.Add(parameterID); 

      cmd.Parameters.Add(new SqlParameter("@PhoneNo", oReservation.ClientPhone));
      cmd.Parameters.Add(new SqlParameter("@UserId", oReservation.UserID));
      cmd.Parameters.Add(new SqlParameter("@Description", oReservation.Description));
      cmd.Parameters.Add(new SqlParameter("@TestId", oReservation.TestId));
      cmd.Parameters.Add(new SqlParameter("@StartDate", oReservation.StartDate));

      cmd.ExecuteNonQuery();

      returnValue = Convert.ToInt32(cmd.Parameters["@ID"].Value);

      return returnValue;
}

Answer 1

You seem to be calling a stored procedure - yet you've never defined your SqlCommand to be a stored procedure:

using (SqlCommand cmd = new SqlCommand("dbo.usp_ClientHistoryItem", conn))
{
    cmd.CommandType = CommandType.StoredProcedure;  // add this line to tell ADO.NET it's a stored procedure!!

If you forget that line, then ADO.NET will try to interpret your stuff as an ad-hoc SQL statement....