Cloudy with a Chance of Insanity: Unsticking iCloud Drive

As with all its services, Apple offers no real troubleshooting when iCloud Drive synchronization stalls in macOS. Glenn Fleishman encountered a problem that took months to diagnose and fix. In the process, he went through the wringer of trying nearly everything suggested online, via Apple support, and from colleagues. In the end, the magic that fixed it was undisclosed engineers.