You have to be signed in on the device with your apple account that is in good standing.
If you just created your apple account, be sure to validate your email address.
Make sure in the Phone app, you’ve got your number listed. On top of ‘Contacts’ you should see your number listed (My Number:). If not, you’ll need to go to Settings → Phone → My Number and enter your number.
Be sure that you have selected the correct time zone on your device. Settings > General > Date & Time
Wi-fi issues can cause iMessage activation problems so have cellular enabled and Wi-Fi turned off.
If it still fails, then in Settings go to General, scroll down to Reset then select “Reset Your Network Settings.
For some users, the message sent out for activation goes out as an international SMS. Try adding $1 to your boot account so you can send intl text messages.
Then there are these workarounds too....
As strange as it sounds, may be you should try this method if nothing else works.
Here’s how it works:
Step #1. Go to Settings → scroll down and tap on Messages and turn off iMessage (also disable FaceTime)
Step #2. Turn on the Airplane mode. Wifi will be turned OFF automatically.
Step #3: Turn ON Wifi.
Step #4. Head back to Messages and turn-on iMessage.
Step #5. You’ll be prompted for your Apple ID if you haven’t added it yet. (else, you don’t get any notification)
Step #6. Now, head back to Settings and turn OFF Airplane mode.
Step #7. Mostly, you’ll be shown a notification that says ‘Your carrier may charge for SMS’ – Tap on OK
Step #8. If not, go to Messages, turn OFF iMessage and then turn it ON again.
Step #9. In a short while, iMessage should get activated.
Step #10. You’ll see a greyed out number and an email ID. A little later, the number should be checked and that’s it.
(This worked, seriously.)
More discussion at Apple’s forum
Apple ID Sign-out, Sign-in
Sometimes, you just need to sign-out of your Apple ID and then login again.
Step #1. Under Settings → Message, scroll down to where it says ‘Send & Receive’ and tap on it.
Step #2. Tap on the Apple ID and then press Sign Out.
Step #3. Switch off iMessage now.
Step #4. Wait for a while (turn on/off Wifi) and then switch ON iMessage.
Step #5. Enter your Apple ID details now and try to reactivate iMessag
If all else fails, do a factoy reset.
Did one of these work for you? Which one was causing issue for you?
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