iMessage on my mac says every contact is not registered with iMessage

I've just done the 10.10.2 update and I've got the problem now. It all worked fine before the update

Did that and it made no difference. Then reverted to 10.10.1 and the problem did not go away. Using 10.10.2 has done something which seems to have caused a problem at Apples end.

When both my phone and computer are awake and someone texts me, the conversation shows in iMessage and I can reply. However I cannot start a conversation on my Mac.

All seems to be sorted this morning. It did ask me to get an application specific password which is new to me. Others have reported that the problem is fixed now on another thread.

This is exactly the situation I have. Only iMessage conversations show up. Regular SMS (text) conversations do not.

Also, SMS Text forwarding is now able to be turned on and working again as well as continuity and phone calling from the iMac

Thanks Gogomilo77. I think that would be a great approach. Looking forward to your findings.

I want to message to people on my computer but it doesent work do you know how to fix it??

All of this is OK for me, and I am still having this problem.

No, the only thing they told me briefly is that my account is challenged, whatever that is supposed to mean.

Engineering has now asked for the log files of my computer to look at and find the issue.

Well, my issue fixed itself this past Monday night....

Yeah, my serial number is still showing up. I will have to give Apple a call and see if they can help. Thanks for the quick reply!

Well, iMessage has fixed itself. Everything seems to be working and syncing just fine. Guess it was on Apple's end. Thanks for the help. I will update again if it breaks.

I fixed it by confirming on my iPhone that message forwarding to my Macbook Pro was enabled. Worked perfectly.