My iPad, iPhone and iMac were all working properly with iMessage. Something changed a day or so ago and now it is not working with iMac.
I would recommend to delete your account from your device and to add it back again. This works in most cases (at least for me).
I don't seem to be able to do that. It's grayed out.
I'm having this same problem. How do you delete it and add it back again?
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