Ok, I had the exact same problem, and after trying to fix it FOREVER... i finally solved it. It does involve going into and editting your registry, which is dangerous and you can easily mess up your computer really bad so this isn't for the faint of heart.
I'm running windows xp pro and am the admin, you must be the admin to do this.
-Go to 'start'
-click on 'control panel'
-double click 'Administrative Tools'
-double click 'Computer Management'
-on the left column, expand the [+] sign next to 'Local Users and Groups'
-click on the 'Users' folder
-now on the right side should be a list of users for your computer. find your profile name and left click on it
-select the 'Member Of' tab
-make sure you are a member of the 'Administrators' group (if not, click 'Add' and a dialog box will open. click the 'Advanced' button. then click the 'Find Now' button. a list of groups will appear, select 'Administrator' then click 'ok'
-now that you're and admin, just close all open windows
-Go to 'start'
-click on 'run'
-in the dialog box type in 'regedit' without the quotes
-now that you're in the registry editor do this:
- click on the [+] next to 'HKEY_LOCAL_MACHINE'
- click on the [+] next to 'Software'
- click on the [+] next to 'Classes'
-now click on the folder 'QuickTimePlayerApp' it may give you and error message, just click 'ok' and ignore it
-with 'QuickTimePlayerApp' highlighted, click 'edit' and select 'Permissions...'
-it will probably give you another error message. just keep clicking ok until you get to the permissions dialog box
-click on the 'Advanced' button
-click on the 'Owner' tab
-select your account name, and check the 'Replace owner on subcontainers and objects'
-click 'ok' and you get another error message, just click 'ok'
-now you should be back to the main permissions dialog box, click the 'Add' button
-in the Select Users or Groups dialog box click 'Advanced'
-then select 'Find Now'
-then select your account and click 'ok'
-this takes you back to the permissions dialog box
-in the bottom part of that box, under Full Control, check the Allow column
you should be solid now, i re-ran the itunes installer again, and got about three more registry key errors that i need to change permmissions on in the registry editor. so just keep open the Registry Editor window and find the registry keys that says you need permission for and repeat the process over and over until you get no more errors and itunes finally installs.
i know it's a pain, but i found no other solution that really worked
Edited by djhedbuzz, 01 April 2007 - 01:12 AM.