video capturing.....am i too stupid or what?

[juggzhead]

i dont wanna sound like a complete noob but somehow i cant get this problem fixed:

how can i play a videofile (any format) with e.g. windows media player (or any other player) and capture that file at the same time?

my capture card is hauppauge win tv go.

any help appreciated
cheers

[UncasMS]

why would you want to capture a file you already have (i.e. which you can play)?