iTunes 10 relaunching after quitting

A couple of MacFixIt readers have contacted us describing a problem with iTunes after upgrading to the recently released version 10. Though the program installs and functions fine, upon quitting, some process will immediately launch the program again.

MacFixIt reader "Aran" writes:

"I can't seem to close iTunes. Every time I close it, it reopens. It seems like a bug that has hit iTunes in the past, but I've never experienced it until upgrading to v10."

This problem may be caused by a number of issues, either with iTunes' configuration or with some system services. Since iTunes 10 is the most recently changed item and is new software, try first troubleshooting its settings.

1. Remove the iTunes preferences file
   A standard troubleshooting step is to remove the application's preference file, and in the case of iTunes it is called "com.apple.iTunes.plist" and is located in the /username/Library/Preferences/ folder. Remove this file and relaunch iTunes to test the settings change.

2. Turn off iTunes-specific sharing features
   iTunes has a couple of sharing features, including Home Sharing and individual playlist sharing. Try turning off these features in the iTunes preferences to see if that helps the issue.

3. Disable iTunes services
   iTunes connects to some online resources, so try disabling or otherwise changing the settings for these. Deauthorize the iTunes Store and turn off the store via parental controls; also disable Genius and Audible accounts to see if those functions are responsible for the problem.

If these options to not help the problem, then iTunes could be continually launched by a problem with some system settings, including Launch Services and the Firewall.

Launch Services are what binds specific file types and communications protocols to various handling programs. If a commonly used protocol is being associated with iTunes, then the system may launch the program whenever it detects the protocol being used.

Though you can clear the Launch Services in OS X manually, there are a number of maintenance utilities that can do this for you. One popular and free one is OnyX, but there are others that can do the job as well. With the services reset, restart the system and then try running and quitting iTunes again to see if the problem persists. Keep in mind that if you reset the launch services, file types will be reverted back to their default handling programs and you will have to set them up again.

You might also take a look at the system firewall, which interacts with many applications' networking protocols and may be causing iTunes to launch if the firewall's configuration is corrupted. Try disabling the system firewall (set it to allow all incoming connections), and also try removing the firewall preferences file. The file is located in the /Macintosh HD/Library/Preferences/ folder and is called "com.apple.alf.plist." With the firewall off, remove this file and then start up the firewall again. You will have to enter the allowed applications in the firewall list again as well as re-enable stealth mode and firewall logging if desired.

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