Multiple_Checkouts Initialization Variable
Specifies Yes to configure the database for multiple users to check out a file at the same time, requiring file merges. Set this variable to No (default) to enable exclusive checkouts, for which only one user has a file checked out at one time. This initialization variable is used in the Srcsafe.ini file only.
Specifies that only one person can have a file checked out at one time:
Multiple_Checkouts = No