Arduino no longer opens ANY INO files

I’ve just been calibrating and configuring my 3D printer with the Marlin firmware. I’d just finished calibration when the Mac that I was using crashed during compile.

Now when I try to open ANY ino file on my computer it just opens arduino with a blank sketch. It doesn’t matter if I try and open from the file menu, or open from finder it will always just load up a blank sketch.

I’ve been trying for about an hour now to find out if there’s some kind of lock file or something which is preventing INO files from opening but right now I’m at my wits end.

I should also mention that I've deleted the Arduino.app and installed again to no avail, I've deleted ~/Library/Arduino too to no avail.

Managed to open a file, but ONLY if it's in the configured sketchbook folder, files outside of that folder still won't open.

Sounds like your Mac needs some attention. PC guy myself, good luck.