Abstract: A computer program, comprising a series of batch processes filed on a separte distribution disk, inhibits an executable program in a disk operating system (DOS). In one embodiment, the batch file of a process, unconditionally ineffective for replicating the functions of the executable program, is transferred from a distribution disk to the computer's DOS and renamed with the filename of the executable program but with an externally executable extension. The DOS file of the executable program is transferred to the distribution disk and renamed with an externally unexecutable extension. In another embodiment, the batch file of the process is conditionally ineffective for replicating the executable program. The user is required to elect, to the exclusion of at least one designated drive in the computer, a drive on which the executable program can be executed.