When I try to sync to my ipad, tons of my music doesn't download. The error message tells me that my ipad is not authorized, but when I try to authorize it, it tells me it's already authorized.... what now?

Question

I want to sync music to my ipad, but it tells me it can't because ipad is not authorized.  when I go to authorize it, it tells me it's already authorized.  I'm confused.

Answer 1

You use the iTunes app, but you authorize a computer to use items acquired from Apple with a specific iTunes account. Then any iOS devices that sync to that computer are also automatically authorized to use the items acquired from Apple when they are synced to the device.
If you are mixing stuff from various usuers individual iTunes accounts it can get a bit confusing. For example if you have apps from thre different users accounts, the apps can only be updated if that user signs into their iTunes account either on the specfic computer or the individual iOS devices.