Installing windows from USB drive helps you to load Windows on PC that don’t have CD/DVD drive. When Installing Windows 7 or Windows 8 from USB Drive If you receive the error “A required CD/DVD device driver is missing” .
Then follow the instructions given below to continue the installation.
Solved “A Required CD/DVD Device Driver is Missing” Error:
Step 1: Connect bootable USB drive to the computer and begin installing Windows using the USB drive.
If you don’t have bootable USB, you can follow our posts How to install Windows 8 from USB Drive or How to Install Windows XP, Vista and windows 7 From USB.
Step 2: When you receive “A Required CD/DVD Device Driver is Missing” error dialog click on Cancel button. This action should take you to the welcome screen.
Step 3: Now, Remove your bootable USB flash drive and insert it back to different USB port. Click install Now again and continue installation process like usual.
This problem happened to all new version of updated Windows 7 installer. I think, it is due to failure of Windows installer to remain its detection to the USB drive. It lost the connection, and became confused, don’t know where to find the USB drive it used to read before.
Hope This Helps You!