I get this error when trying to install any Apple application on my Windows XP machine at work: "The older version of apple software update cannot be removed". Apple's Software Update program will not auto update itself and iTunes will not uninstall.

The solution is to download the Windows Install Cleanup program from Microsoft. I had to remove Apple Software Update, Itunes and Quicktime. Since I don't use iTunes on my Windows machine, I didn't worry about backing it up. But if i did use it, would have backed it up.

I went back and reinstalled all the Apple programs without any problems