There's no simple way to recover the file.
You should not exit WinSCP if you have unsaved changes. You should reconnect and save again.

Also make sure you use the latest version of WinSCP.

One user hat the page open before it was lost, so I managed to get the most of html and js back. The php was mostly on other files, so everything good. :)

My uni has computers that we can access from home. I do that with winscp.
So, I was editing my scheduler.php file and then I tried to saved (done that numerous times). Now, the save could not be completed and a message for abort popped up. I clicked on it, exited winscp and then logged in again and the file has lost all its data. The file is very very important to me!!!
It wasn't deleted, but it has 0kb data inside it.
How can I retrieve it, pleasE? :( :( :(