I can send and receive messages from my desktop app to iMessage registered users (the message shows a blue background). But when I send to an Android phone, for instance, it get the red "!" and it won't send. If I do this on my iPhone - to the same Android phone number - it works fine.
What do I need to do to my Desktop App to get it to work? Actually this used to work, my update to High Sierra seems to have been when it stopped working.
Thanks
See the SMS/MMS section of this support document regarding Continuity. Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support
See the SMS/MMS section of this support document regarding Continuity. Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support
I had to go to my iPhone and allow iMessage to work on all my devices (which it used to do. I think when I installed High Sierra it blew it all away somehow).
This worked:
On iPhone, go to Settings > Messages > Send & Receive. Make sure that the Apple ID at the top of the screen is the same Apple ID that you're using for iMessage on your other devices. Add a check to your phone number and email address, so that you can be reached by iMessage at both. Do the same on your iPad or iPod touch.
THEN...
On Mac, open Messages, then choose Messages > Preferences. Click Accounts, then select your iMessage account. Make sure that the Apple ID shown here is the same Apple ID that you're using on your other devices. Add a check to your phone number and email address.
I have spent probably 12 hours on the phone with one Apple Care senior advisor about this exact same issue over the course of the past 2 weeks. It has involved sending numerous screen shots to Apple Engineering to prove to them that all of my Settings are correct, which they are. And I spent 3 hours on the phone with my carrier, AT&T, yesterday, just trying to ascertain if the problem might be with the carrier, since, like you, I used to be able to send SMS texts to any Android from both my Apple laptop and iPad. In my case, that stopped working on the same day my AT&T cell number was "spoofed". A coincidence? Doubtful, but could be. If Apple Engineering can come up with a solution, I will try to find this thread again and advise you of the fix. The AT&T techs were completely clueless. They couldn't even properly restate the problem. They never could grasp it. Sheesh!
And no, the document on Continuity was of no help. I already had all of the Settings entered correctly.
Yes, I had already verified those settings. That was not the problem. Neither Apple nor I yet know what is causing the issue.
SMS messages won't send on iMessage Desktop App
