A small number of Mac users are reporting that the latest version of iTunes, 10.1.1, has locked them out of iTunes altogether.
iTunes 10.1.1 was released last Wednesday to provide "a number of important bug fixes".
Among the issues fixed were issues with Nvidia GeForce 9400 or 9600 graphics cards not displaying video properly and syncing problems with the iPod, iPad and iPhone.
However, Apple Insider reported that several Mac users had found that after applying the update, iTunes crashed immediately after being opened.
To fix the issue, it is recommended that you download iTunes directly from the Apple website instead of through the automatic Software Update and overwriting the previous installation.
iTunes 10.1.1 is available for both Mac and Windows systems though the problems are thought to only affect Mac installations.