If Me.chkCreateNewEvent.Checked = True Then
            Me.grpNewEvent.Visible = True
            Dim StartDate As Date = Today
            Dim StartTime As Date = Now
 
            DTP1.Format = DateTimePickerFormat.Custom
            DTP1.CustomFormat = "dddd, dd.MMMM.yyyy"
            DTP1.ShowUpDown = False         
            DTP1.Value = StartDate
            '------------------------------------------
            'ohne Sekunden????
            DTP2.Format = DateTimePickerFormat.Custom
            DTP2.CustomFormat = "HH:mm"
            DTP2.ShowUpDown = True
            DTP2.Value = StartTime
...

            Dim eventStart As DateTime = Nothing
            Dim eventEnd As DateTime = Nothing
 
            If chkAllday.Checked Then
                eventStart = DTP1.Value
                eventEnd = DateAdd(DateInterval.Day, 1, DTP1)
            Else
                eventStart = DTP1.Value & " " & DTP2.Value
                eventEnd = DTP3.Value & " " & DTP4.Value
                'umwandeln CurrentCulture Uhrzeit (Derzeit => de) in US
                eventStart = ConvertDateTimeToCulture(eventStart, _
                  System.Globalization.CultureInfo.CurrentCulture.Name, "en-US")
            End If