How to completely disassociate iMessage from my device? I have an older iPhone that I was thinking about selling soon in order to get a new one. I've set up iMessaging on the device.  Normally I would just erase the phone a couple of times and be done with it.  But recently, there has been exposed a glitch in iMessaging whereby users continue to receive other user's iMessages, even after the sim card is removed, and the phone is erased.

So I'm curious: is there any way to prevent this from happening?
Go into Settings -> Messages and halfway down choose Send and Receive.
Tap your AppleID on the top of the page, sign out, and let the new guy sign his or her self in.