Hi, am a Sketchup newbie. Am trying to transfer files between Mac laptop where the file was created, to both desktop Mac, and PCs. by saving the drawing onto a USB. All machines are running Sketchup Make 2017. Transferred the .skp file into the default directory on each machine, but each time I try to open it, it give the above message. It then says xx file could not be opened. Why does Sketchup not recognise the .skp file? Very frustrating. Have tried several different drawing files, on different USBs, so don’t expect it to be a corrupt file issue? Have also tried to import the file, from the USB, with the same error message.