Help with Bootable USB drive

Can I make a bootable usb copy of windows 7 from a computer that already has windows 7 on it or do I need to already have the disc to make the bootable usb drive?

I always create a bootable windows usb drive using a iso image of a windows disc and a program from pen drive linux called universal usb installer. But if your computer has a hidden partition where the recovery disc can be created from you may be able to create a iso from that but I wouldn't know as I have never tried to retrieve one.

Good luck.

You can download the iso from Microsoft for free: pick your version from this handy list of links. You'll need a license key though. If it's not on a sticker on your computer somewhere, there might be a tool to read it from the system. I don't know off the top of my head. EDIT: Here you go.

They also have a tool for creating a bootable USB installer from the iso. Get it here.