Cannot acess Norton Bootable recovery tool

I cannot acess the norton bootable recovery tool on someone's computer. The owner of the computer has a Norton 360 installed, she said her pc might be have a hidden vius that can't be scanned by Nortan 360. So, I am trying to acess to the Norton Bootable recovery tool and cannot acess. The computer's first boot device is from cd drive. I inserted a Norton CD and restarted the computer and tried to boot from the CD but it says: "Cannot boot from CD. Error Code 5." S, the computer starts the windows.

 

Why like that?