Lost file after read only

Hope someone can help. Accidentally opened file in sketchup 2016 while working on same model in 2017, opened as read only & now file disappeared & can’t find anywhere…

You should still have a backup file, labelled .skb in Windows or ~.skp on Mac.

Try searching for the filename if you can’t see either.

Thanks for your help again John, much appreciated. The only .skb su files that come up on windows search are 2 from a year ago. Somehow, i think the file has been obliterated out of all existence! Been using su pro for 9 years & never totally lost a file… then again I’ve never opened same file in 2 versions of su at same time either so maybe a real no no… would think it would be somewhere though?