IFO files from DVDs do not contain any multimedia data, so it is not possible to convert ifo to wav or any other audio/video format for that matter. You would need to convert the actual video, represented by a .vob file.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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