A .mnu file is a Menu File. Several programs use this file extension. DVD-Lab & DVD-Lab Pro use this file to save and load user created menus. DVD-Lab is DVD Authoring software developed by MediaChance. DVD-Lab allows you to convert compatible MPEG-1 and MPEG-2 files to DVD files (VOB, IFO, BUP).
To load a .mnu file in DVD-Lab, select any Menu (VMG or VTS menus) in the Project Window, then click Menu --> Load Menu. The saved menu should now replace anything that was already on that particular Menu.
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DVD-lab is a new DVD authoring tool which combines a modern professional interface with easy to use approach and it gives the user freedom to create what they want.