A. XP, Windows 2000, and Windows NT don't contain DOS, although XP can create DOS-bootable disks. All three OSs support the cmd.exe command shell, which lets you run NT-equivalent DOS commands. In XP, go to Start, Programs, Accessories or click Start, Run, then type

cmd.exe

to start the command shell. For older application support, you might want to try the command.com shell, which is more compatible with MS-DOS than cmd.exe is. In XP, click Start, Run, then type

command.com

to start the command.com shell. Command.com can call autoexec.bat and config.nt, both of which are located in the \windows\system32 directory, just as MS-DOS calls autoexec.bat and config.sys. If you're having trouble running your old DOS command-line programs from the cmd.exe environment, try running them inside a command.com shell.