FashionistaSunny Said:
"imessage issue on IMAC: I'll ask her in the am when she gets up.: What I don't get it is it goes through on the phone, so wouldn't that be the same thing? It's only when I select to send her a message using the IMAC that it doesn't go through?"
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More Thoughts:
No, as your number is you number. She may be blocking you out (though not intentionally).
But, if it is not going through on your Mac, then here are three thoughts:
I. Boot Into Safe Mode:
[Hold Down: the shift key upon boot]. Keep holding it down until you reach the log in screen. Then, log in, wait 30 seconds, and then boot up normally. In Safe Mode, damaged system files (i.e. caches) are fixed, and replaced.
II. Try New Admin User:
On your Mac. try creating a new Administrator User, and see if you can configure it with the new user. If it then works, then it is likely something configured in your current user. Delete the user when all is fixed.
III. Reinstall the MacOS:
So, as a last resort, reinstall the macOS. You would backup your Mac, and then reinstall it. Nothing would be removed. It's just that items that have been moved or corrupted, would be placed back to where they should be or replaced, respectively. But, more on that later, if it comes to that. I look forward to hearing back from you. Keep us up to date.