You need to
- launch Terminal [Applications/Utilities], then type or copy/paste
chmod +x[including a space after the x] - then drag the app you need to change the perms straight onto the Terminal window, which will fill in the correct path
- hit Backspace once, as the last task will add an unnecessary space
- Then you need to add the sub-path to the actual executable inside the app, so copy this & paste it onto the end of your current Terminal line
/Contents/MacOS/* - Hit Enter
This will change the permissions to executable.
An example of the 'finished' Terminal command, using TextEdit as the example
chmod +x /Applications/TextEdit.app/Contents/MacOS/*
Note:
Terminal never tells you "Success" or "Done" etc. If you see it add a new line saying
yourMac:~ yourname$ then it's finished.
If there's an error it will report that.
If you get an error saying you do not have permission to do this, then start over, but use
sudo chmod +x for the first step.
This is, in effect, "Administrator Override" mode.
You will be asked to provide your Mac password when you hit Enter [which will not show at all as you type it] then hit Enter again.
https://superuser.com/questions/1127274/the-application-exampleapp-can-t-be-open...