here is how you might be saved
this happened to me once. I don't know how but here is how i fixed it.
go to your user under the home screen
go to library
go to app support
go to address book
in there you should find a file that says previous save.
make sure to check the date to see if it is older the the problem.
also set you sync to notify you if there is a change in your computer of 5% or more in the settings.