Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button2.Click
        If IsNumeric(TextBox1.Text) = True Then
            Try
 
                Dim cmd As New OleDbCommand("INSERT INTO Scans (Maschine, 
Datum, Uhrzeit, TubNr) VALUES('" & Label3.Text & "', '" & 
Format(Label2.Text, "hh:mm:ss") & "', '" & 
Format(Label4.Text, "dd-mm-yy") & "', '" txt_TubNr.Text  "')", Con)
 
                Con.Open()
                cmd.ExecuteNonQuery()
                txt_TubNr.Text = ""
                Me.Hide()
            Catch ex As Exception
                MsgBox(ex.Message)
            Finally
                Con.Close()
            End Try
 
 
 
        Else
            MsgBox("Bitte geben Sie eine Nummer ein!")
            Me.ActiveControl = TextBox1
 
        End If
 
 
    End Sub