.PBB File Extension
What is a PBB file?
Phonebook file used by various mobile phones; contains backup data exported by software at a local AT&T store; typically stored on a USB drive after an AT&T representative has exported the phonebook file.
PBB files can be opened using CellBrite Content Manager by selecting Contacts → Open Phonebook. They may then be exported to Outlook or Outlook Express by selecting the menu option Contacts → Open Phonebook.