I had this god awful problem and I went about it every which way but here is
the fix.
I have an old computer and I rebooted and itunes wouldn't load because it
didn't have the base layers of information to work off of.
1.Go to
http://www.oldapps.com/itunes.php?old_itunes=12.Download itunes 4.1 first then itunes 5 then 6 then 7.5
3.You will be able to run 4.1,5 and 6 no problem because it is a basic basic
setup.
4. In order to run 7.5 which is the key one because otherwise it won't read
your ipod you just need that foundation that you just built.
5.Voila... it will work and you will thank me.
6.If it doesn't work first delete everything in your add/remove programs
that has to do with apple,itunes,quicktime and bonjour. Also delete
everything in your C drive/program files that any apple,itunes stuff exists.
7.I also installed the latest windows installer 4.5 from thewindows website
before hand but I don't know if that had anything to do with this.
So don't cry itunes will be yours again.