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PSA: Have ‘damaged’ Mac App Store apps today? A quick reboot should fix it

Mac App Store error

The Mac App Store noticeably experienced some problems last night / early this morning with downloaded apps. Upon opening affected apps, the system would say that the app is ‘damaged’ and cannot be opened, just like the examples from Graham. It certainly seems scary at first glance.

The error message recommends reinstalling your apps individually. While this will fix the problem, it’s a pain to do and isn’t necessary at all: your apps are fine, but the error message makes the situation sound far worse than it is. To simply fix the problem, just reboot your Mac, running OS X Yosemite or El Capitan, and the problem will ‘magically’ go away.

The more interesting question is, why did this happen at all?

The bug arose because the Mac App Store security certificates expired today, as explained by Paul Haddad from Tapbots. This means that the system could no longer validate the application packages as the downloaded certificate was expired.

The OS’s only choice was to stop the app from launching entirely. Unfortunately, the accompanying error alert wasn’t very specific and made it sound like a far bigger issue than it actually was. There is no permanent ‘damage’. If you follow the prompt to the word, re-installing all your apps will remedy the issue, but it isn’t necessary.

Some users got slightly different errors, such as having to re-authenticate with the App Store but all had the same end goal of causing the store certificates to refresh, resulting in the issue going away. You don’t even have to reboot if you don’t want to … but it’s the easiest ‘one sentence’ solution.

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  1. 89p13 - 7 years ago

    Same type of message was received when I attempted to install the latest Firefox Beta via TestFlight on my iPhone – Said the vendors Certificate was no longer Valid. Worked fine several hours later.

  2. geek45 - 7 years ago

    I had that problem with one of my apps yesterday.

  3. Gregory Wright - 7 years ago

    Had the problem with 1Password yesterday. The reboot didn’t work but a reinstall fixed the problem.

    • aaronh - 7 years ago

      I didn’t even know the rebooting was an option yesterday, but the delete/reinstall for 1Password worked for me as well.

  4. I restored my iPhone from iCloud last night (at a Genius Bar appointment, no less)

    I lost all my health data.

    Many of my apps no longer launch. Kayak, Desert Golfing, and 1Password crash on launch. Apple Store hangs on a white screen. My Heart complains about a bad database.

    All my apps think they’re launching for the first time, as if they have either no data or bad data.


  5. Interestingly, this was not an issue on El Cap Public Beta 2 (well, now 3). I have a few of these apps and was not prompted to do anything differently.

  6. Zoran Sanković - 7 years ago

    That is not entirely true. I still have problems with some apps even after rebooting the system. So please don’t give false information! Some applications still not working even after reinstalling. So problem is not solved yet!


Avatar for Benjamin Mayo Benjamin Mayo

Benjamin develops iOS apps professionally and covers Apple news and rumors for 9to5Mac. Listen to Benjamin, every week, on the Happy Hour podcast. Check out his personal blog. Message Benjamin over email or Twitter.