Possible Duplicates:
Lost info by syncing iPhone to new computer?
Backup and restore iPhone
I would like to sync my iPhone content with my new Mac (i.e. contact, calendar, apps, etc.) but the first sync will erase all contents from my iPhone.
Is there any way to avoid it?
If the iPhone backup has been performed on the old PC, can I restore all the content from the backup if the content was erased during sync with the new mac?