HT4759: iCloud: System requirementsLearn about iCloud: System requirements
Currently Being ModeratedDec 26, 2012 4:23 AM (in response to smithy 8)
Welcome to the Apple Community.
Not sure what you mean by advanced mail address, but providing you mean the non @iCloud addres (which can't be changed), then:
Firstly, you need to change your details with Apple, Start here, change your country if necessary and go to manage your account.
In order to change your Apple ID or password for your iCloud account on your iOS device, you need to delete the account from your iOS device first, then add it back using your updated details. (Settings > iCloud, scroll down and hit "Delete Account")
Providing you are simply updating your existing details and not changing to another account, when you delete your account, all the data that is synced with iCloud will also be deleted from the device (but not from iCloud), but will be synced back to your device when you login again.
In order to change your Apple ID or password for your iCloud account on your computer, you need to sign out of the account from your computer first, then sign back in using your updated details. (System Preferences > iCloud, click the sign out button)
In order to change your Apple ID or password for your iTunes account on your iOS device, you need to sign out from your iOS device first, then sign back in using your updated details. (Settings > iTunes & App store, scroll down and tap your ID)
If you are using iMessages or FaceTime, you will also need to log out and into your ID there too.