macOS won’t load

[Dazzlepants]

My SSD drive from my old MacBook Pro 2012 has been installed into a new MacBook Pro (also 2012). The SSD was partitioned between windows and macOS but only windows will load. I can see both in disk utility but the main partition of macOS is grayed out and it says it’s unmounted. I want to avoid a full reinstall if possible as I’m not sure everything is backed up. I’d really appreciate a solution if anyone has ideas!

 

[MichaelDT]

First try to reset smc. Then if that doesn’t work try to repair the disk in disk utility. If that doesn’t work try to reinstall OVER your old install, this will preserve all your files.

Also it’s macOS not iOS.