I am using Sketchup Make 2016 and every time I save a file I am able to re-open it but when I send it to a friend they get an error message saying that the file was created in 2017 and cannot be opened (they are using 2016 Pro).
I have had the 2016 make on my computer for a few years now. The problem began recently when I installed 2017 Pro trial and then uninstalled a few days later. After uninstalling 2017 my computer seems to still think its installed. If I right click a sketchup file the only open with option is Sketchup 2017.
I would love to be able to share 2016 files again.