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I try use a windows form's text box to display the fax status but it was not allowed. Any idea?

Private Sub faxman_status(ByVal sender As Object, ByVal args As DataTech.FaxManNet.FaxEventArgs) Handles faxman.FaxStatus

Label1.Text = args.Fax.Port.ToString

Label2.Text = args.Fax.FaxStatus.ToString

End Sub

Regards,

Please define "not allowed".  I'm not sure what you mean by that.

Most likely you are getting an InvalidOperation exception which is actually being thrown because of an inner exception with the following message: 

The FaxStatus event fires from a background thread and therefore, being on a separate thread from the user interface, cannot be used to update the controsl on the UI.  This is something we may correct in future releases of FaxMan SDK.  But for now here's a workaround:

1. Modify the FaxStatus event to use BeginInvoke:

         Private Sub faxMan1_FaxStatus(ByVal sender As Object, ByVal args As DataTech.FaxManNet.FaxEventArgs)
            frmModemStatus.UpdateStatus(args.Fax)

            If InvokeRequired Then
                Dim aArray(1) As Object
                aArray(0) = args.Fax.Port.ToString()
                aArray(1) = args.Fax.FaxStatus.ToString()
                BeginInvoke(New MyDelegate(AddressOf UpdateStatusDisplay), aArray)
            End If

            Try
                TextBox1.Text = args.Fax.Port.ToString()
                TextBox2.Text = args.Fax.FaxStatus.ToString()
            Catch ex As Exception
                System.Diagnostics.Debug.WriteLine("ex = " & ex.ToString())
            End Try

        End Sub

 2. Define a new delegate:

         Delegate Sub MyDelegate(ByVal faxPort As String, ByVal faxStatus As String)

 3. Create the callback method referenced in the BeginInvoke method:

        Private Sub UpdateStatusDisplay(ByVal faxPort As String, ByVal faxStatus As String)
            TextBox1.Text = faxPort
            TextBox2.Text = faxStatus
        End Sub