Lately I have noticed a lot of people complaining that their iTunes no longer works after installing Windows 7. The solution to this is usually a very simple one:

If you have recently to 64-bit Windows 7 you will need to download the 64-bit version of iTunes. You can find it here: http://support.apple.com/downloads/…

If your iPod Touch stopped syncing with your iTunes, try this:

In iTunes under Help click for Check for updates and get the new Mobile Me. You can also search for the latest version of the Mobile Me and download it.

You can also click Run Diagnostic which is under “help”. That checks for the problem and has some solutions.