iPhone 4 and iTunes sync problem..

[technics100]

I'm trying to sync my wife's iphone with itunes. It syncs fine at the minute, but there isn't anything on the iphone apart from apps. If I try to sync some music or movies it says "the iphone is synced with another library, do you want to erase and sync"

This also happens if I click the manage music manually button..

Any ideas?

What is wiped if I choose the erase & sync option? everything? emails, contacts etc?

 

[urdygurdy]

is iphone new?? have you synced it up with another or second computer?? Are you using itunes with 2 different iphones or ipods??

 

[technics100]

iPhone is not newl, it was synced with another computer but has since been synced with this computer. When plugged in it will sync, but when I try to add anything it says erase and sync..

 

[lawrenceots]

I think erase and sync just deletes media etc. I'd transfer all the media across, then sync it back and ensure its all on. Then make sure you do a backup in itunes of the iPhone, then it should all sync and backup correctly.