There's a couple of different things I can think of that might be going on.
One is that the installation has become damaged, and when you try to launch iTunes it's trying to do a repair install (consistent with the UAC message you're getting), but the repair is then failing silently.
Can you check something for me? Head into your Uninstall a program control panel, select iTunes, and click "Repair". Does the repair install go through okay or do you get an error message? If you get an error message, what does it say? (Precise text, please.)
Hello b noir!
I did what you suggested, chose to repair itunes. it ran through it's little thing, I did not get a message. I restarted my computer and was able to get into itunes thru the icon. I then closed out itunes and tried to get in again and was DENYIED! I got the same message : If i wan to allow this program to make changes 2 this computer, program name is Apple, verified publisher is Apple Inc. I do notice that there is a windows shield? on the icon itself on my desktop.
Odd that it is launching fine once after the repair.
We'd better check to see if it's a compatibility mode issue.
Try the following document, only be sure that none of the boxes in the compatibility mode tab are checked (not just the compatibility mode box itself):