A friend of mine had an android phone, then he got an iPhone and his number changed. I deleted his old number and saved his new number. I created a text message to him and iMessage picked it up as being a number that iMessage can work with. He had his phone for about a month and decided to go back to the android.
Now, everytime I send him a message, my iPhone wants to send him an iMessage but he clearly does not have iMessage anymore. Its the same number he had on his iPhone. However, he has gone into his iTunes account and there is no trace of an iPhone being registered to it. The phone has since been turned in at BestBuy mobile, master reset, and sent back to Apple.
I can long-press the message I send him and chose "Send as Text Message" and after a few times it defaults to that seemingly for the rest of the day. But the next day, or after some time has elapsed, it wants to send an iMessage to him again. It is becoming a real pain to send him messages. I don't want to disable my iMessage as I have a lot of friends with iPhones and I enjoy the ease of iMessage. But I can't stand the fact that my phone insist that I send an iMessage to his number when his number is going to an android device. He does not own a Mac and there are no other iDevices that he can register a phone number to (that I know of). I know he does have an iPod and its for his wife. Honestly, he may not even realize that his iPod has iMessage on it and it could be registered there.
My question is what can I do, or what should he do, to remedy this problem and have my phone send him normal text messages instead of iMessages?
I have an 16GB iPhone 4S, he had the exact same thing.
EDIT: More information. Yes, I have deleted his contact data from my phone, and iCloud contacts several times to try and remedy this problem. It doesn't help.