How to Unregister/Deregister iMessage

You might need to deregister iMessage if you have a non-Apple phone and can't get SMS or text messages someone sends you from an iPhone.
This can happen if you used iMessage on your iPhone and then transferred your SIM card or phone number to a non-Apple phone (such as Android, Windows, or BlackBerry).

If you recently switched from using an iPhone and didn't turn off iMessage, your number is still sending iMessages, not SMS or text.


 You have two options:
If you still have your iPhone go with these four steps
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