MCH

Thanks so much Brian, the instructions on the link worked, even though PS had previously been ticked. I just unticked and re-ticked the PS program. Will have to remember to do this if it plays up again.

why? It cost ???

No wonder I'm confused. We are having 2 conversations .... one about layers and masks and another about system information and crashes. System info here Mac Mojave. Computer about 5 years old.

What do you mean where am I? At home in Sydney. Just about to go out though.

I have CS5 Photoshop on my Mac which was upgraded to Mojave (10.14.6). I can open PS but it crashes almost immediately so unusable. Any help would be greatly appreciated.