iMac
I’m trying to set up my Mac computer and when it tells me to put in my apple-id I put everything in correctly and it says “Unavailable please try again later.” :(
iMac, OS X 10.11
Sounds like this could be an internet access issue? Have you determined that your are live on the internet and can normally visit other web sites? Try your apple ID to log onto iCloud from Safari, for example, just to convince yourself that your ID is valid. Your description though, does not sound like this is the problem. I saw the same thing you describe on a recent setup, and trying again later did in fact work as expected, so I thought no more about it. Good luck.