Phenoprotect produces read errors directly on the CD-ROM in areas which do not contain any game data, but can be checked by programs. CD Writers report these as unreadable sections. There areas cannot be copied to the hard drive.
The specific software, e.g. the game and the InstallShield used for installation can, however, contain instructions from the software manufacturer to check this erroneous data, if this data is not found when the program started, it is not an original version and the game or installation is terminated.
Windows 9x operation systems cannot read the erroneous sections. Any attempt to copy will result in the operation system aborting the process.