Model locking allows you to disable changes to your model. To toggle model locking, simply select Protect/Unprotect model from the Proc menu. When you first lock the model, you will be prompted to enter a password (of at least 4 characters). To unlock a previously locked model, simply enter the previously entered password.

Once password protected, a number of features of the model are locked down. Notably, the text view of the model cannot be accessed, all existing scenarios become write-protected, equations and variables cannot be added/deleted or modified, links cannot be broken, and add-factors cannot be assigned or modified.

Note that the model may still be solved, new scenarios can still be created, modified, and deleted, and you may create an unprotected copy of the model.