DXG Technology DXG-580V HD - Manual (Page 52)

If you select Delete All, press the scroll wheel inwards to
display the submenu.
3. Use the scroll wheel to select √ and press the scroll wheel
inwards to delete.
4. Press the MENU button again to exit the menu.
Note: Once deleted, files cannot be recovered so make sure
you have a backup before you delete. Files that have been
protected will not be deleted. You have to unlock the files first
before deleting them.
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