So I bought a great new MacPro as the iMac was getting pretty slow. I exported the iTunes program to the MacPro and moved the external drive where the music files live to the new MacPro. Everything looks & works fine when I am using the MacPro to play files, etc. But when I try to synch to either new iPhone or old iPod classic, I get an error message saying that the library used to be on a different computer and it will need to copy over the entire device and that I'll lose my purchased files. There must be a workaround for this, right? Apple cannot expect me to re-buy every time I get a new Mac? Or can they?