The user list in VSS Administrator allows you to control who has access to the VSS database, as well as what level of access they have. VSS Administrator lets you add and delete users from the user list, assign access rights to specific users, and change their VSS passwords.
When you add a new user, VSS automatically creates an SS.INI file for that user based on the default SS.INI template in the \VSS\Users folder. You can modify this template file to create a different default SS.INI file for each new user. For more information, see Customize SRCSAFE.INI Files
For information on how to maintain the VSS user list, refer to: