Why isn't iMessage working on my mac?
Hello,
Every time I try to send a message from my computer, immediately a red exclamation point pops up and it says not delivered. I am connected to wifi so I know that it's not a connection issue. I've allowed text message forwarding for my computer from my iPhone so I don't think that that's a problem. I've enabled my account for messaging on my mac and it says that iMessage is active and that I can send messages. The one thing that may offer something is that when I sign out and sign back in again, it usually says that there has been an authentication error, and it gives me a pop up notification on my phone that my appleid is being used on a new device even though I've been signed on to my computer since I got it. I have the latest version of the macbook pro and it is running macOS High Sierra (10.13.2).
Thanks!
MacBook Pro with Retina display, macOS High Sierra (10.13.2)