7.5 Upgrade Created Itunes Black Hole

Question

*Thank you Apple!* Your 7.5 ituens has killed ITunes on my computer and you offer no support.
I absentmindedly clicked on Upgrade to 7.5 which loaded but when it was rebooting - it somehow created a obnoxious noise through the speakers and froze my computer requiring me to hard crash. When I rebooted - Itunes no longer works. Problem is - it created an endless loop of deadends to fix.
When I re-download 7.5 - it loads and posts a meaningless message" Feature you are trying to use is on a network resource that is unavailable." Options offered: Click OK = nothing. Second option "Browse for itunes.msi" One finds many of these files and I can even find the ".msi" in the 7.5 download. None work. New message says the "itunes.msi is not a valid installation package."
Thinking that I must remove the older version and start fresh - one uses the control panle / remove ITunes = one gets sent back into loop looking for "itunes.msi which is then reported "invalid."
Hoping to somehow get rid of old itunes and not lose music and computer limit.
With the amount of money Apple makes off of itunes - they should offer some free support!

Answer 1

+When I re-download 7.5 - it loads and posts a meaningless message" Feature you are trying to use is on a network resource that is unavailable." Options offered: Click OK = nothing. Second option "Browse for itunes.msi" One finds many of these files and I can even find the ".msi" in the 7.5 download. None work. New message says the "itunes.msi is not a valid installation package."+
+Thinking that I must remove the older version and start fresh - one uses the control panle / remove ITunes = one gets sent back into loop looking for "itunes.msi which is then reported "invalid."+
This isn't an iTunes 7.5 thing. All those messages are familiar from earlier versions of itunes.
Let's try the following procedure.
First, head into your Add/Remove programs and uninstall your QuickTime. If it goes, good. If it doesn't, we'll just attend to it when we attend to iTunes.
Next, download and install the Windows Installer CleanUp utility:
Description of the Windows Installer CleanUp Utility
Now launch Windows Installer CleanUp ("Start > All Programs > Windows Install Clean Up"), find any iTunes and/or QuickTime entries in the list of programs in CleanUp, select those entries, and click “remove”.
Next, we'll manually remove any leftover iTunes or QuickTime program files:
(1) Open Local Disk (C:) in Computer or whichever disk programs are installed on.
(2) Open the Program Files folder.
(3) Right-click the iTunes folder and select Delete and choose Yes when asked to confirm the deletion.
(4) Right-click the QuickTime folder and select Delete and choose Yes when asked to confirm the deletion. (Note: This folder may have already been deleted if QuickTime was successfully removed using Add/Remove Programs earlier.)
(5) Delete the QuickTime and QuicktimeVR files located in the C:\Windows\system32\ folder. Click Continue if Windows needs confirmation or permission to continue. (Note: These files may have already been deleted if QuickTime was successfully removed using Add/Remove Programs earlier.)
(6) Right-click on the Recycle Bin and on the shortcut menu, click Empty Recycle Bin.
(7) Restart your computer.
Now try another iTunes 7.5 update. Does it go through properly? If so, does iTunes launch properly again?