Although both .pptx and .ppg files represent presentation documents created in Microsoft PowerPoint, a pptx to ppg conversion does not seem very likely. This is due the fact that .ppg files appear to be pretty old and not supported in newest versions of PowerPoint and the old version of PowerPoint won't support the latest .pptx files, so there is no way to convert pptx to ppg directly.
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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