P4s Bsci Versions 2.93 & 2.85, Problem Starting The Application:

someone please help me, i just downloaded p4s versions 2.85 and 2.93 to aid my preparation for bsci exam, but the application never got started , an error is popping up that "COULD NOT FIND MAIN CLASS.PROGRAM WILL EXIT" from Java Virtual Machine Launcher and i have Java Runtime installed on the sysytem and others p4s are running,  how can i solve this problem, ?