I use keynote on my MacBook Air for some kinds of presentations. I’m trying to convert a file I saved as .odp to a keynote presentation. I have saved the odp file as a pptx file. When I try to open the pptx file in keynote I get an error message that the file can’t be imported because the file type is invalid.
Hello,
have you checked https://www.apple.com/mac/keynote/compatibility/. This tells me, that keynote is not fully supporting .pptx file. Same is certainly true for the export of .odp to .pptx (See warning This document may contain formatting or content that cannot be saved in the currently selected file format “PowerPoint 2007–2019 when exporting .odp to .pptx. So there are two conversions required to get that to keynote and there is a good chance that it doesn’t work.