If you bought the Photoshop Elements Editor from the Mac App Store and you’ve tried to use it in the past couple of days, you’ve discovered that it’s not working. Instead you see something like this:
Before this, you may get a weird message that you originally downloaded PSE on another computer and you need to sign in to authorize it on this one, even though you know it’s not true.
It’s not anything you did, nor is it the result of some update to El Capitan (10.11). Everyone is having this problem with all the App Store versions on all versions of OS X, and for now there isn’t really a solution.
Evidently there was a problem with expired security certificates that made practically everything from the App Store (not just PSE) stop working the other day, but it’s supposedly fixed now. However, I can confirm that the fixes you will find posted all over the Internet, like here, for example, don’t work for PSE at all, at least not for anyone I know who’s tried them:
First of all, unless you have PSE 13 (the latest App Store version), don’t uninstall PSE unless you have a backup copy someplace.
When Adobe releases a new version of PSE for the App Store, the older one becomes unavailable for download in the future. EDIT I see they’ve changed this; in the past I could not download older versions again, but now the App Store does make the old versions available, a great improvement.)
(You should always keep a backup copy of the App Store versions; normally you can reinstall them by simply dropping the PSE folder into the Applications folder on another Mac. Note that this only applies to the App Store version, not at all in any way to the regular download or disc versions of PSE.) Adobe does offer downloads of older versions on their website, but those all require a serial number for installation, which you don’t have, since your Apple ID takes the place of a serial number for the App Store, so that doesn’t help you, either.
It appears that most App Store apps are fixed, although Elements is still majorly broken. For whatever it’s worth, I have one other App Store application (a silly game that is quite old) that also remains broken, so it’s not totally just an Adobe problem.
Right now all I can say is that Adobe is investigating this, but so far there is no fix for it. When they get it figured out, I’ll post the solution for you.
If you bought PSE elsewhere, either as a download or on disc, it should be working normally, and any problems you might have aren’t related to this particular issue.