This drive is currently in use or contains mounted volumes. Please unmount these volumes and press OK. - Discribe message received when attempting to select source drive.
If you receive this message it means that the MAC OS has control of the disc in the drive so Discribe cannot access it. Eject the disc by dragging the mounted disc icon on your desktop to the Trash. Close Discribe and reopen it. Select your job type again. NOW put the source disc in the drive and close the drive tray. With Discribe open, it will automatically gain control of the disc in the drive.