installation of itunes 11.5.1 failed. I get the following message "errors occurred during installation before Itunes could be configured. Your system has not been modified. To complete the installation run the installer again. So I tired agian and again

I went into control panel unistalled apple mobile device support, apple software update, apple application support,and bonjour. I rebooted and tired again failed same error. removed the apple programs again went into registry and deleted and reference to apple or itunes. deleted files in program x86 directory, common files. reboot reinstalled failed. any suggestions?

Using 2 ipad airs need at least 11.1 cannot new itunes but can insta;ll old versions but that will not work with new ipads..