I've founded a backup that was crated when switching between Router and Layout.
The work is partially saved, still what happened for me remain unacceptable.
Already happened to me.
What is the size of the PCB file you are trying to read ? I bet you it is 0 ...
Then, there is nothing you can do ... that is why I activate Auto Backup.
I agree ... this is not acceptable ...
No the .pcb file still contains the information (is more than 1 MB). And I controlled with a couple of file editor.
But since the program has crashed when I was writing the file (I was creating a ground plane) something went wrong.
But really, in any other program that I know, this shouldn't be enough to corrupt the file. Not in 2018 (I'm using PADS VX, it's about 4 years ago).
That does not save you because when you open the corrupted file, Pads overwrite the three backup, corrupting them also.
I got the same poblem. No words.