It doesn't seem likely that a presentation could be converted to a spreadsheet as these two document formats serve different purpose. You could of course copy the tables, text or images from PPTX to XLSX from Powerpoint and paste it to Excel, but that is hardly conversion that can be done automatically.
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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