We recently upgraded a user’s Intel Mac from Tiger (Mac OS X 10.4.11) to Leopard (Mac OS X 10.5.6) and everything went smoothly except for his iPhone. Under Tiger, the iPhone worked as it should syncing from iTunes on a regular basis. However, once we upgraded to Leopard, his iPhone wouldn’t show up in iTunes! When we checked the System Profiler and selected USB, the iPhone showed up. So we tried all the different USB ports, repaired permissions, etc, but nothing seemed to work.
The solution, as we discovered, was to re-download and reinstall iTunes. It seems that there are some system components that are installed by the iTunes installer that are system-specific. So when iTunes was installed in Tiger it all worked fine. But when we upgraded to Leopard, the iTunes components needed for the iPhone to work in Leopard were missing. Re-installing iTunes under Leopard installed the missing pieces.
