installation - Can`t install ubuntu 12.10 from usb stick

Have a laptop with x64 amd, 3 gig ram, win 7.
Downloaded the desktop iso file 12.10 x64 from ubuntu website.
Also universal usb installer and unetbootin win.
When I finished the first step => load the iso file in universal usb installer to my usb stick and then restart with usb stick in the usbport, bios not find the usb media. I have changed the usb to boot as nr 1, harddrive as nr 2 in bios.
Also tried with the 32 bit ubuntu verson and unetbootin but dosen´t work?
Press F#9 when boot and bootmenu comes up and only harddrive with win 7 is available to choose, usbstick dosent shows up.
Whats wrong?