Q: I am running Lion on my 27” iMac. I have the box “Open iTunes when this iPhone is connected” checked, but iTunes has to be manually started to synch my iPhone 4. ANy clues why this rather simple problem occurs?
A: The first thing to check is to look in your iTunes Preferences on the “Devices” tab and ensure that the option to “Prevent iPods, iPhones and iPads from syncing automatically” is not selected. This option serves as a global override to the individual options for each device, and if enabled will prevent ANY device from automatically syncing with iTunes, regardless of whether it is a new or existing device.
If this option is not enabled yet you’re still having problems, try UNchecking the “Open iTunes” option, syncing your device, and then RE-checking it. This option is actually stored with the device and it’s possible for the option in iTunes and the setting on your iPhone to mismatch, particularly if you’ve connected your device to other iTunes libraries.
Failing this, the only remaining option is a potential problem with your operating system or installation of iTunes. Removing and reinstalling iTunes can sometimes solve this—to do this simply move the “iTunes” application to the trash, empty the trash and then download the latest version of iTunes and install it. Note that you can do this without losing any of your iTunes preferences or content as you only removing the application and not any of the data.