Messages on my 2014 iMac not working after OS X 10.10 update and iOS 8 GM update...
Messages on my iMac aren't working after the recent updates. Non iOS texts are going to or from my iMac or iPad Air.
"not registered with iMessage"
I've tried a lot of things, logging out/logging in, reboots, etc, and I'm getting the notification on all devices saying they're using iCloud, iMessage and FaceTime.
I posted this on the iOS developer forum. With a couple of glitches, all my iOS 8 beta versions were good. This is the first time a key feature hasn't worked.