Open a PPS-file
How do I open a PPS file produced by PowerPoint or the backup tool 'Pack and Go'?
.PPS files, when opened, automatically launch the slide show. At the end of the presentation, the file is closed and it is apparently impossible to edit or modify it.
In fact the difference between a normal .PPT presentation file and a .PPS "import presentation file" is only the last letter of the extension! All you need to do is rename the file to .PPT and you can edit the presentation just like a normal one.