Apple’s SSL certificate that is responsible for verifying and authenticating connections to Apple’s Mac App Store software update servers has expired, causing the Mac App Store to issue errors like those above. Another error notification points to the swscan.apple.com server as being the issue, below.
A quick search shows that this SSL certificate expired yesterday May 24th at midnight.
Third-party app updates appear to be working — I was able to update three different apps, though I did encounter the above issue. Dismissing the error and updating the apps works just fine. However, official Apple updates apparently do not work. Apple does make these updates available through their website.
While the SSL expiration seems likely to be the culprit, the issue could also be something else.
We’ve reached out to Apple to try and clarify what the problem exactly is, and when the issue will be resolved. We have yet to receive a comment.
Thanks anonymous for the tip!
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