iMessage keeps popping up How can I disable the iMessage pop up when I turn on my Mac? It keeps asking me to sign in with my Apple ID. I don't want to set it up because I don't want to use iMessage. But the box keeps opening every time I turn on my Mac and it is getting frustrating as I have to go through 3 pages before I can turn it off.
I had to contact apple support for this solution. The fact that it is not intuitive implies a usability bug. The reason for the prompt is a keychain entry under either login or local items. Basically after removing all entries with the text 'apple' in them I was able to restart and login with no facetime or imessage prompts to login. I hope this helps.