The CDFS file format typically relates to software installed on a CD. However, you can copy these files from a CD and place them onto other locations on your computer or, even, onto an external device, such as a USB flash drive. If you currently have a CDFS file on your USB drive, you can remove it. Doing so saves valuable hard drive space on your portable memory device.
Connect your USB device, such as a USB flash drive or external hard drive, to an available USB port on your computer.
Select "My Computer" (or "Computer" in later releases of Windows), and double-click on the removable USB device icon. This opens a program window with all of the files currently saved on the portable memory device.
Navigate your way through the USB drive to find the CDFS file. Right-click on the file icon, and a drop-down menu appears.
Select "Delete." A window asking you if you are sure you want to remove the file from the drive appears. Click on "Yes," and the CDFS file is deleted from the USB drive.