Wondering if anyone is having the same problem I am having. I'm almost 100% certain its related to installing Yosemite and usingiMessage on it.
I was using iMessage successfully on Yosemite Beta for a few hours. After which I switched back to my Mavericks system but when I tried to use iMessage it will not sign in. I have tried changing the password but still not working. Its working fine on my iPhone. If any one can point me in the right direction it would be great.
Thanks in advance