Normally, you cannot use USB devices when working in a real mode environment (MS-DOS) or Safe Mode (in earlier versions of Windows). To do so, you must first install USB legacy emulation drivers, and Legacy USB support must be enabled in CMOS.

Some computer and motherboard manufacturers may have Legacy USB support or USB Keyboard Support in CMOS setup disabled. If this option is present, verify it is Enabled if you want to enable Legacy USB support.

  • How to enter and exit the BIOS or CMOS setup.

If you cannot locate this option in CMOS, and you cannot located USB drivers for your device, contact the computer’s hardware manufacturer.

Enabling the option in CMOS only supports computer keyboards and mice, without additional drivers. Other USB devices, such as printers or CD-ROM drives, or any other devices may also require additional DOS drivers to be fully detected.

  • See our USB definition for further information and related links.
  • USB help and support.