1. i add the assembly reference
2. modify stireport code
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Data;
using Stimulsoft.Controls;
using Stimulsoft.Base.Drawing;
using Stimulsoft.Report;
using Stimulsoft.Report.ReportControls;
using Stimulsoft.Report.Components;
using HighlanderLibrary;
namespace Reports
{
public class Report : Stimulsoft.Report.StiReport
{
HLFirebirdUtils fb ;
public Report()
{
this.InitializeComponent();
}
but i get the following error :

error CS0122: 'HighlanderLibrary.HLFirebirdUtils' is inaccessible due to its protection levels
inside the HighlanderLibraries are public classes