When iTunes freezes, the program can no longer play music and any downloads stop. Sometimes, your computer may have limited RAM -- random access memory -- with too many programs running at one time. In that case, close the other programs and restart iTunes. If that doesn't help, there may be larger problems with iTunes or your computer drivers.
Force Program to Close
When iTunes freezes, sometimes forcing the program to close and then reopen may resolve the problem. If clicking the "X" in the top right corner of your iTunes window does not close the program, hold down the "Control," "Alt" and "Delete" keys on your keyboard and then choose "Start Task Manager" from the menu. Highlight iTunes in the list of running programs and hit the "Delete" key to force the program to shut down.
Importing and Syncing Problems
If iTunes freezes while you are importing files from an audio CD or syncing with an Apple device, such as an iPhone, you may have an outdated version of iTunes. After you force iTunes to close, reopen it and click the "Help" tab at the top of the window. Click "Check for Updates" to initiate a search for a newer version of iTunes software. If you are unable to get to the "Help" menu because iTunes freezes again, close the program and go to the Apple website to download the latest version of iTunes.
A larger issue with your computer can cause iTunes to freeze. Keep your antivirus up to date so that you catch any viruses early. Confirm that iTunes is allowed through your computer's security firewall or the program cannot function properly. According to Apple, if the drivers on your computer are out of date, iTunes may not run properly and freeze up.
When iTunes freezes during a gapless playback scan, the content itself probably caused the problem. If you want to resume the scan, you need to determine which song files are corrupt. The process can be arduous if your library is large. Start by closing iTunes and going to the iTunes folder on your computer's hard drive. Move "Library.itl" to your desktop and then reopen iTunes. Your iTunes library will now appear empty. Go to the "File" tab and choose "Add Folder to Library." Navigate to the folder that contains your music. Apple recommends adding only one song or artist back to the library at a time. Redo the gapless playback scan each time. If iTunes freezes again, you know the files you just added caused the problem.