iTunes v.8 (which is required for my new ipod) will not install on my computer and I have ran all of these diagnostic checks and have upgraded up to service pack 3 and have uninstalled, reinstalled and even defraged my computer and it continues to post an error saying,

"The Windows Installer Service could not be accessed. This can occur if you are running windows in safe mode, or if the Windows Installer is not correctly installed."

My computer is not running in safe mode and the only program that the installer isn't installed correctly for is itunes.