I have one error with itunes (error -2096)

Question

...and it does not open. The error says:
QuickTime Unavailable
QuickTime is required to run itunes. Please reinstall itunes
I have reinstall itunes a lot of times, I have the last version available for download, the QuickTime works. I don’t know what’s happening

Answer 1

Try and use Microsoft's Cleanup Utility and then reinstall Quicktime/iTunes:
http://support.microsoft.com/kb/290301
Make sure it's a new and fresh download from:
http://www.apple.com/itunes/download/
See if any of these help:
http://docs.info.apple.com/article.html?artnum=302538
http://docs.info.apple.com/article.html?artnum=302386
http://docs.info.apple.com/article.html?artnum=302775
If not mentioned in the articles, make a new user account in Windows and see if iTunes opens. That will tell you if there's something funky in your main account (if the new user works), or if you have a system-wide issue.