That's one way to do it. But it also tells us that the problem was permissions, without telling us where the problem existed.
Hopefully next version we can spend some time on providing more specific error messages in these cases (tell me the @#%@#% directory with the problem).
If you are the only user on the system, then ignore permissions should be fine.
to fix this is very simple, close photoshop and illustrator,either check the scratch disk "ignore ownership on this volume" by right click on the scratch disk and pick Get Info OR use a software like Onyx to show Hidden files and folders (start onyx go to Finder tab, check Show hidden files and folders) then open your scratch disk and delete .TemporaryItems, on mine i removed a bunch of files that shows as greyed out files and were created over the years only the .Trashes cannot be deleted but to be on the safe side just deleting the .TemporaryItems will do
restart photoshop now you can use your scratch disk or set it again without getting the error. good day
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