the installer didn't find the iso file

["abdelkader belahcene" <abelahcene@gmail.com>]

Hi,
I used the kernel from hd-media and put the cd1 iso in the usb.
I followed the directions to install linux from usb, it ran correctly , I mean the boot, choice of keyboard , language, the iso file. 
Then the system couldn't continue it searched for the CDROM !!!??     It seem that the path for packges is the CDROM instead of  the USB!!

thanks for help