Help! Driver is missing.

Hello,


I get the error below when trying to install Windows 7 ultimate on my late 2013 retina mac book pro right after the windows install starts up and I select my language. What can I do?


Thanks!

"A required CD/DVD drive device driver is missing. If you have a 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."