Trouble w/ OS update

Hey can someone help me out? When I hold down the window button as the MPC powers on, the last two sentences say:
"OS file searching....
A correct OS file wasn't found."

I downloaded the file off the AKAI Pro website. The files show up on the CF card, but why won't it upgrade the OS? Thanks in advance.

did you un-zip the file before putting it on the card?

also, it has to go into the root directory (not in a folder)