Microsoft File Replication Service Diagnostics Tool provides a graphical interface to help troubleshoot and diagnose problems with the File Replication Service (FRS). FRS is used to replicate files and folders in the SYSVOL file share on domain controllers and files in Distributed File System (DFS) targets. FRSDiag helps to gather snap-shot information about the service, perform automated tests against that data, and compile an overview of possible problems that may exist in the environment.