This driver is needed to play a cd on windows 3.1. IF you double click on media Pleyer icon and you get the a masseage MCI device driver missing then you need this driver for sure. I am not sure if you need these other two [MCI] MIDI Sequencer and Sound drivers to use the CD-ROM to play a cd. after downloading it put it in a floppy disk then go to Program Manager under File chose Bun then Browse then under Drivers chose A \ and there is a little window that say "List Files of Type" scrowld down and All Files you will get 4 files chose the readme.txt for instructions on how to run the file. Once at the window that ask you to put the disk chose browse and chose A \ drive and click on the folder once then click on Ok Clik OK again and it will star to extract the file.