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Earlier this week Mac App Store (MAS) apps, on launch, were showing up as “damaged” and couldn’t be opened. The old MAS security certificate seemed to have expired and a new one, at first, didn’t seem to be showing up. Here’s my current understanding of what happened.

Some consider this just a minor mistake on Apple’s part while others see it as endemic to the Mac App Store situation. Regardless, I’m told Apple is working hard on a fix and will have something “soon”.