Hi all, wondering if anyone can help. 
I've put a new hard disk into my computer and I'm trying to installed Windows 7 from a USB stick. I've made my USB bootable by following this guide.
I set the USB as a primary HD and then set it as first boot option in BIOS. It gets me past the screen where I select my language, then on the next screen I get the Setup is starting... screen.
After about 5mins I get a popup:
Thanks, hope someone can help. Way to spend a Friday night, huh!

I've put a new hard disk into my computer and I'm trying to installed Windows 7 from a USB stick. I've made my USB bootable by following this guide.
I set the USB as a primary HD and then set it as first boot option in BIOS. It gets me past the screen where I select my language, then on the next screen I get the Setup is starting... screen.
After about 5mins I get a popup:
A required CD/DVD drive device is missing. if you have a driver floppy disk, CD, DVD, or USB flash drive, please insert it now.
Note: If the Windows installation media is in the CD/DVD drive, you can safely remove it for this step.
Thanks, hope someone can help. Way to spend a Friday night, huh!