The phone number "is not registered with iMessage"

Nancy and Chris,

I am having the same problem. I haven't been able to send text messages from my 2010 MacBook Pro now to non-Apple device users for almost a full week now. I finally have the time to troubleshoot this, but my iPhone 5 doesn't seem to have 'text message forwarding' on my iPhone message settings. I have the latest iOS running on my phone (I think 10.2 I believe)? So I'm not sure what the issue is.

Glad it worked, Nancy. What I found mystifying was how it got toggled off in my phone in the first place. But I realized after I had posted the above (in which I mentioned that I had just updated my version of Sierra on my Mac) that I had also updated the iOS on my phone to 10.2.1. Moral: after an update or upgrade, maybe one should look at all one's settings in any way connected with icloud, mail, etc., on all devices.

Thanks for the reply.

This number has been in my Contacts for over 15 years and I was texting fine from the computer until High Sierra. Messaging from iPhone works. It's just the MacBook that has stopped working.

Thanks again.

Had exactly the same issue recently, ways to solve it:

- sign out from iMessage on computer (messages => preferences => accounts => sign out)

- sign out from iMessage on phone (settings => messages => toggle "iMessage" off

- sign in to iMessage with applID on phone (settings => messages => toggle iMessage on, click on "use appleID for iMessage)

- sign in to iMessage on computer (messages => preferences => accounts => sign in)

- close and reopen messages on computer, works

if yo add them to your mac address contacts and fill you witch emall severice they use IE Google AIM IT Seem to work. you must be log in and have set up you imesages service. I works with hangout too.

This same problem recurred again for me (iphone SE, iOS 10.2.1), curiously enough after I had updated my macOS on my desktop Mac to 10.12.3. After an online 'chat' with an Apple advisor, I looked on my phone at Settings/Messages. On my iphone SE, Text Message Forwarding is the second item down, and on touching it, it turned out that it had mysteriously been toggled 'Off' without my having touched it. Talk about connectivity!

But toggling it back 'On' restored my SMS messaging as well as imessaging.

It seems that if one types a message on one's Mac to someone who is not imessage-enabled, it first goes to one's own iphone, which converts it to SMS and sends it on to one's addressee. Or am I making that up?

As I said in my previous post, you won't find it in 'iphone'. You'll find it in Settings/Phone.

Curiouusly enough, it has got toggled off again in my phone, and I am having difficulties toggling it back on. But that seems to be another story...

this is what worked for me too. i also turned lots of the settings off and on. signed out of my apple account on my phone in messages and on again. I basically did everything but also turned all the messages off and on but the one thing that worked was actually turning Facebook off and on again

I called Apple Support. After spending time going through the lower level advisor, then being transferred to a senior level advisor, I discovered the problem and simple solutions.

Problem

The iPhone can send message via iMessage or SMS ( SMS for non Apple phone like Android)

The Mac can only send message via iMessage NOT SMS. So you can't send messages directly through a Mac to a non apple phone.

Solution

If you link your iMessage on your Mac, to your messages on your iPhone , you can send messages on you Mac to non Apple user, as the message will be automatically be routed through your iPhone and be send as SMS.

This is How to Link Mac Messages with iPhone Message

On your iPhone (not your Mac)

Go to "Settings"

Go to "Messages"

Go to "Text Message Forwarding"

Turn on your Mac to allow linking

This should work - It solved my problem.

For me to get to the delete person from Chat I had to double click on their name in Messages to get to them in Contacts, then click on the phone number in Contacts to try and send a text, then do the delete from conversation. This is not an exact process, there is some alchemy and unknown steps that may have worked in getting it to work. Still in the dropdown in Messages it says phone number - iMessage but it actually sends as SMS text. All this started for me after I get a random alert I need to change my iCloud password, then the whole secret key thing, 2-step verification, etc. Took over an hour of my work day for absolutely no reason.

As an add-on to JeffcNick's good point, if you have multiple devices, you may need to turn on Message-Sharing in your iPhone for ALL of them. For example, I had this problem on my MBP (always worked then suddenly stopped) and Message-Sharing was already activated on my iPhone. It was off however for my work and personal iPads. As soon as I switched them back on for the iPads, hey presto i can message Androids from my MBP again.

This is clearly a bug and Apple need to fix it.

With IOS 11, each device must be linked to your iPhone.

Go to your iPhone Settings > Messages > Send & Receive.

Make sure your iPhone number is checked. Go back one step in messages

"Text Message Forwarding" should now appear if it dEid not before.

Select Text Message Forwarding. There is a list of all your other iPad(s) and iMac.

Slide button over for one of your other hardware items (iPad or iMac).

A message will appear on your other device with a numerical code. Enter that into the query box on your iPhone.

Press "Allow" on the iPhone. This turns on the iPad or other device.

I have 3 iPads and an iMac. So I had to do this for each device.

• I've been texting this individual from my MacBook for months. This morning I get the "not registered" message.

• I can text this number from my iPhone but not the MacBook.

• The MacBook displays the message I send from the iPhone but won't send to this number.

• I can text other numbers. Seems to be something about this number.

Q1:Why OK from the phone and not the computer?

Q2: What does it mean to register a particular number?

(1) Ensure your iPhone is on the same WiFi network as your computer first of all.

(2) On your iPhone:

(a) Go to "Settings";

(b) Go to "Messages".

(c) Next, go to "Text Message Forwarding". Your computer or other device should be shown in the list- just click it to turn the switch green.

(d) Have fun texting anyone from your computer via iMessages.

I have had this problem multiple times. One fix I just figured out today is to make sure that the phone number you have for your contact is listed as a mobile number in Contacts on your Mac/IPad, other device. I had some entry mistakes that my iPhone doesn’t seem to notice that my Mac did. Once I had entered the number correctly as a mobile number, then I had no problem sending them texts via iMessage.