If you have the optional QuickTime MPEG-2 Playback Component installed with QuickTime 6 or later, you can play back video in Video Object (VOB files), which are used in the DVD-Video specification and contain the mutiplexed audio and MPEG-2 video data.
Sometimes QuickTime Player needs a little help to recognize VOB files when opening them from the Finder. If a VOB file doesn't open by simply double-clicking it, do these steps:
You don't have privileges to change the application for this document only. Do you want to change all similar documents to open with the application "QuickTime Player?"... then click Continue.
This should set Mac OS X to open VOB files in QuickTime Player whenever you double-click them in the Finder. The MPEG-2 Playback Component may ignore the audio portion of the stream, but the video will play back normally. Please note that the component will not play back encrypted VOB files, such as those found on commercially-produced DVDs, in QuickTime Player.
304656: "QuickTime MPEG-2 Playback Component plays only first 4 GB of file"
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