DOS programs print by sending instructions to the printer. Windows programs print by sending instructions to the operating system, and it is the operating system that sends instructions to the printer. For this reason, when you set up a printer you set it up to print in Windows and then all Windows programs can use it because all printing is channeled through the single printer set up in Windows (your operating system). Just because you have set up your printer in Windows does not mean that DOS programs will be able to use it. These DOS programs bypass the operating system and attempt to drive the printer directly. Frequently they are not to good at it and a DOS program may for example be incapable of making a color printer print in color.