What is a BAK file? A .BAK file also serves as a database backup file generated by Swiftpage Act!, which is a customer relationship management (CRM) software. This file includes a duplicate of an Act! database (usually an .ADF file), effectively preserving essential data such as customer contacts, company details, group information, notes, historical records, and activity data stored within the database. Swiftpage Act! Swiftpage Act! is a software application used for customer relationship ma...