I have the exact same problem. However, if I try signing with my old apple ID, or even my brothers apple ID, both of those work with iMessage. I have called apple over a dozen times at this point and they have thrown me through 3 or 4 different processes each time. Then they bumped my issue up to a senior advisor, then to engineering in which i had to wait a couple days for them to get back to me. After they heard back from engineering, they called me back and asked me to screen share with them, in which I hung up. The I waited a couple days and called them back, speaking with a new person and opening a new case. That person said that he unblacklisted my ID from being tagged as a "Suspected commercial spammer", and that once I got home to my mac, it should now work. I got home, and it still didn't work. A couple days later, I called again. The person I talked to this time put me on hold to speak to a senior advisor. However, this time, when they asked, I gave them the serial number from my real mac, and the error code from my Hackintosh. (The previous time I gave them the fake serial from my hack, and both times, they told me that my serial wasn't showing up in their system and I could be using a non-apple computer or clone). After giving them the serial from my real mac (and telling them that iMessage wasn't working on my real mac) they told me that they are going to re-register all of my devices for me so that everything works. They said it should take 24 hours for it to kick in. It has now been 36 hours and still no success. Over the last couple phonecalls, the apple agent did say that he couldn't find anything specifically wrong or flagged with my apple ID. This was after the first phonemail in which they said i was a "Suspected commercial spammer". So at this point, I am at a bit of a loss. I don't know how many more times I can call apple before I'm having them dig so deep that they will figure out I'm using non-apple hardware. Its just weird that every other apple ID I use works! Have you tried using a different apple ID? If a different one works, then you know your configuration settings are most likely legit, and its most likely something to do with apple back-end on your apple ID. If anyone has any suggestions for me, please let me know. I figured I would share my experience though just in case it helps you.
