Why Macs around the world have failed to launch third-party applications

For a while, starting at 4:00 PM ET, Apple Mac users around the world who have tried to open third-party applications have noticed strange errors and slow launches, applications that didn’t start completely.

These errors existed regardless of whether users had installed the latest macOS Big Sur update, and based on testing, it appears that the problem with launching applications is related to Apple’s US Gatekeeper technology detecting if the software is safe to use on Mac.

Jeff Johnson, a Mac and iOS developer, confirmed that the operating system has some irregularities when connecting to an Apple server and that blocking it by modifying the hosts file could solve the situation.

The errors don’t seem to exist now, but as TechCrunch points out, servers may have been overloaded when people upgraded their Macs to Big Sur and suddenly launched requests to re-authorize older applications.

Engadget contacted Apple in the US for details on the reason for the errors, but the answer did not appear. On the development system status page, Apple from the US confirmed that a problem with the notary service appeared between 3:00 PM and 5:09 PM ET.

On the support page covering Gatekeeper, Apple says, “If you download and install applications from the Internet or from a developer, macOS will continue to keep your Mac safe. While installing Mac applications, plug-ins, and installation packages from outside the App Store, macOS checks the developer ID signature to see if the software is from an identified developer and if the software has been modified.