"file missing..." means ** QuickTime is missing. you have problem of installing QuickTime. usually "error -3" came out at the end of stallation of QuickTime which means QuickTime does not install well. iTune 6 needs QuickTime to open it.
Do the following steps:
1).All you can do is run "iTunes Setup" again to remove iTunes and QuickTime. well, error alert is still coming out (don't mind). Then iTunes'll be removed.
2).Go to
http://support.microsoft.com/kb/290301/
to carefully read and download "windows installer clean up utility package". save to desktop.
3).disable all your VirusScan, Personal Firewall, Spamkiller, Privacy Service..in system tray on task bar.
4).run "msicuu2" got "window stall clean up", run it, carefully just select "all user...QuickTime", click "remove".It'll remove "QuickTime".
5).go to control panel-add or remove programs. Click "QuickTime" and remove.
6).searching all the file and folder in your computer for "QuickTime" and "iTunes". delete all their files as you can.
7).empty recycle bin and restart computer.
8).when window finishs reboot, disable all virus protection softwares as you did before.
9). run "iTune Setup" again. you will get complete installations of iTunes and QuickTime.
i went through all this few days ago.
