A process and system for activating various programs are provided in a personal computer. The computer is initially provided with a registration shell. A data link is established between the personal computer and a registration computer. By providing the registration computer with various information, a potential licensee can register to utilize the program. Once the registration process is complete, a tamperproof overlay program is constructed at the registration computer and transferred to the personal computer. The tamperproof overlay includes critical portions of the main program, without which the main program would not operate and also contains licensee identification and license control data.