export and email

Hi

I am using this code to email report as attachement. But report attached as "untitled.txt" instead of "untitled.pdf".
Can any body guide me what to change in code, that attachement should be "untitled.pdf"

thanks in advance

Code:

---

        Dim ExportOptions As New CrystalDecisions.Shared.ExportOptions
        Dim EMailOptions As New CrystalDecisions.Shared.MicrosoftMailDestinationOptions
        Try
            ExportOptions.ExportFormatType = ExportFormatType.PortableDocFormat
            ExportOptions.ExportDestinationType = ExportDestinationType.MicrosoftMail
            EMailOptions.MailToList = txtEmail.Text
            EMailOptions.MailSubject = "Online Report"
            EMailOptions.MailMessage = "Report..."
            ExportOptions.ExportDestinationOptions = EMailOptions
            CrReport.Export(ExportOptions)
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try

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