iPhone 15 synching issues with iTunes account
I have a new iPhone 15 and am trying to connect to my old iMac to synch some of my 75,000 songs on my system. I plug in my usc cable and get a message that I need to download a software update. Every-time I try this option I get a subsequent message, indicating that it cannot install software because it’s not currently available from the software update server.
i tried updating software, but get a message “6 incompatible updates”
macOS Sierra ver. 10.12.6
stumped