I recently upgraded my Curve to a newer operating system (4.5.0) and I have 'lost' my address book. Any ideas where it went and more importantly, how do I get it back?
Do you still have the address book application and just the entries are gone? Check to make sure you don't have filters (check options) sifting out all of your entries.
One time I upgraded the OS, none of my data was restored but my backup was available.
If you have a backup, restore it. If you have sync'ed to Outlook, you can sync back to your BB.
