export crystal report to excel

[tendaimare]

i am trying to export a crystal report document to excel but it is giving me an error saying that object refference is ...
Any help pliz

Sub cryview()
        'This code contains a functionality to export to Excel
        '* A sub for every corresponding Crystal Report
        Dim rpt As New CrystalReport3()
        Dim strExportFile As String = "c:\TestExcel.xls"
        Dim sql_personnel As String = procesSQL(txtSQL.Text, cmbTableName.Text)
        Dim dt As New DataTable
        dt = MyFormz.cl_Class.SelectRows(sql_personnel)
        ReportTitle = rpt.ReportDefinition.Sections(0).ReportObjects("txtReportTitle")
        ReportTitle.Text = strTitle
        ReportPhone = rpt.ReportDefinition.Sections(0).ReportObjects("txtReportPhone")
        ReportPhone.Text = Me.txtPhone.Text
        Users = rpt.ReportDefinition.Sections(4).ReportObjects("txtUser")
        Users.Text = strUserDetails
        rpt.ExportOptions.ExportDestinationType = ExportDestinationType.DiskFile
        rpt.ExportOptions.ExportFormatType = ExportFormatType.Excel
        Dim objOptions As ExcelFormatOptions = New ExcelFormatOptions
        objOptions.ExcelUseConstantColumnWidth = False
        rpt.ExportOptions.ExportFormatOptions = objOptions
        rpt.SetDataSource(dt)
        rpt.Export() '<<<< Object refeerence not set to instance of an object 
        CrystalReportViewer1.ReportSource = rpt
        objOptions = Nothing
        rpt = Nothing

    End Sub