Can't open any file in Photoshop!

FWIW I was having the same problems mentioned in several comments above. Even that of CC not acknowledging that I even had all the apps on my computer. So I did what I used to always do as my first precautionary measure…I zapped my PRAM. After doing so the computer finished booting and CC was then telling my PS needed to be updated (all other apps were normal). I updated. Then I double-clicked on my file, held my breath…and the file opened. Error seems to be gone.

I have the same issue. I've deleted the .psp file and I'm using Photoshop CC 2018 which was recently updated to version 19.0.1.

I can't open anything, and when I try to create a new file, the tools doesn't respond.

Can you access the cooler settings from the Edit menu?

I'm sure you've done this, but worth a double check.

Quit Ps, hold in Mac: Command, Option, Shift while starting up Photoshop.

Keep the keys in till you get the dialog.

A dialog box will appear asking if you wish to delete the preferences/settings file.

Choose Yes.

HTH

reset your preferences -   https://forums.adobe.com/thread/375776

[moved from Adobe Creative Cloud to Photoshop General Discussion]