Check that you have installed the latest version of iTunes. Right-click the iTunes application, and select “Properties” or “Get Info” (depending on your operating system). A window will appear that gives all of the software information, including the version number.
Visit Apple.com and click “iPod + iTunes.” You will see a download button for the latest available version.
Upgrade your iTunes version if it is not the most recent one available by clicking the download button and following the instructions that walk you through the download process.
Visit Apple.com and download the iTunes software as described in the previous section. Even if your computer already runs the latest version of iTunes, your particular iTunes application may be corrupted.
Click the installer to reinstall the software. The installer will lead you through the download process and replace your copy of iTunes with a new version of the software.
Open iTunes to check that the installation worked and see if it resolved the launch issue.
Drag the “iTunes Music Library.xml” file to your desktop. You will find it in the "iTunes" folder on your computer.
Delete the iTunes library file from your “iTunes” folder.
Click iTunes to see if it opens. If it does, the launch issue has been resolved but you will need to finish re-creating your library.
Select “Import Playlist” from the “File” menu. Choose “iTunes Music Library.xml” from your desktop to finish the re-creation.