Question: iMessage keeps not delivering on iMac
I got a new SIM card/phone number and since it's been installed, iMessage won't work on my iMac desktop. I don't know if it's a coincidence and unrelated to my new phone number or not, but the timing definitely coincided. I am running 10.13.1 on the iMac. iMessage will work for various periods of time (a day or two, an hour or two), then inevitably I get a "Not Delivered" message. Usually if I sign in and out of iMessage, or sometimes close everything and restart the computer that gets me up and running again, but the problem persists and is driving me batty. Never any problems on my phone. Thanks for any tips.