1.2 to 1.2.2 problem

Hi,

I'm trying to update from 1.2 to 1.2.2
My forum is installed in oyre.net/forum
I've made all is said in install.html
I try to execute oyre.net/forum/12_to_122_update.php
It gives me an error: "This file must be run from the forum root directory."

what's the problem?

Thanks,

Ludo,