Validate a time span interval application setting

Private Sub PropertyGrid1_PropertyValueChanged(ByVal s As Object, ByVal e As System.Windows.Forms.PropertyValueChangedEventArgs) Handles PropertyGrid1.PropertyValueChanged
    Select Case e.ChangedItem.Label
        Case "Interval"
            Dim OneMinute As TimeSpan = New TimeSpan(0, 1, 0)
            If e.ChangedItem.Value < OneMinute Then
                MsgBox("Inteval too short, setting to 1 minute.")
                My.Settings.Interval = OneMinute
                My.Settings.Save()
                PropertyGrid1.Refresh()
            End If
    End Select
End Sub