can't play ayumi video dvd

[nepa1st]

i have puchased ayumi music video dvd and when i try to play it in my power dvd 6 it wont play, i dont have any problem when i play a movie dvd.
when i check in the windows explorer i notice that all the .vob file size was 0 kb.
and when i play it on dvd player it could play with no problem

could anyone help me...