private void ExtendVolumeForm_Load(object sender, EventArgs e)
        {
            long numberOfExtentBytesAvailable = ExtendHelper.GetMaximumSizeToExtendVolume(m_volume);
            long numberOfMBAvailable          = numberOfExtentBytesAvailable / 1024 / 1024;

            numericAdditionalSize.Maximum = numberOfMBAvailable;
            numericAdditionalSize.Value   = numberOfMBAvailable;
            btnOK.Enabled = (numberOfMBAvailable > 0);
        }