My.Application.DoEvents()

    Private Sub setText(ByVal [text] As String)
 
        If Me.TextBox1.InvokeRequired Then
            Dim d As New setTextCallback(AddressOf setText)
            Me.Invoke(d, New Object() {[text]})
        Else
            Me.TextBox1.Text += [text]
            My.Application.DoEvents()
        End If
    End Sub