maybe your copy is bad, (downloading stuff like games is generally bad)
what windows are you using?
how are you doing this cmmands? dus promt? full dos mudus?what are your system specs? are you sure this is the right folder?

also:
not:
this tells it too, you missed the folder, else it would have said:
i think the last solution will probably solve your problem, but the others might be necesary. jj1 wont work on xp/pentium4 unless you have special software.