A digital contents distribution system that generates first execution verify
logic,
second execution verify logic and execution verify logic conversion software. The
first execution verify logic and second execution verify logic each carry out the
verification and execution control of contents, and the first execution verify
logic is linked with the contents at first. The execution verify logic conversion
software includes execution verify logic converter for replacing the first execution
verify logic with the second execution verify logic to relink the latter with the
contents. A user terminal is provided with the contents linked with the first execution
verify logic, and the execution verify logic conversion software.
