How to add license without License manager?

To check out a license for PLECS, enter: [success, message] = plecs(‘checkout’)If the check-out succeeds, the return variable success will be set to 1 and message will be an empty string. Else, success will be set to 0 and message will contain a detailed error message. When called without left-hand side arguments, the command will raise a MATLAB error upon an unsuccessful check-out and else execute silently.

If you execute the command and a license is already checked out then the behavior is the same as the checkout succeeding.