A method and system that enables efficient migration of security and other user data from one operating system environment to another in a large distributed authentication environment by keeping all critical data in sync between the two operating system environments. Specifically, synchronization of password and user data can be achieved during migration of password data from a first operating system platform to a database of a second operating system platform over a prolonged period of time without disruption of service, while allowing the users to (1) continue accessing the system resources, such as print and file services during the migration and (2) change/update passwords and other profile information.