Constant requests to sign in to imessage
Hi,
I'm having a problem on my MacBook Pro, where every time I start up my computer I am asked to sign in to iMessage (actually called Messages on the Mac, but well done Apple for creating an incorrect login screen as well as a non-essential app I can't delete).
I have never logged in to Messages. I never want to log in to Messages. I don't know anyone I would contact via Messages. I do not have any other Apple products so I would never care about syncing.
Please can someone tell me how to stop these stupid messages? I have to quit the screen 3 times every time I boot up my computer because it appears at 5 minute intervals. I can't access the app Preferences tab because I don't have, nor want to have, this app set up on my computer. I have switched off the 'handover' option under General in System Preferences.
If I need to do something in Terminal, could someone give me the steps, please? I have deleted things before but I'm not confident I'll know what I'm looking for or what the search term(s) should be.
Thanks in advance for any help you can give.
MacBook Pro 15", macOS 10.13