I'll bet you are trying to run that program under MS-Windows version XP or newer? If that is true then you can not run that program on your os. Install Win98 or MS-Dos Version 6.X and try again. I know that's not what you want to hear but that's the breaks when you use an ancient obsolete 16-bit compiler on modern MS-Windows. It's like trying to put a model T engine in a 2010 car -- won't work.
or (if you insist to use something that old, which is idiotic in 99% of cases, very few people have to maintain software that old and those that do know how to do it) use virtualisation to run an old operating system in for example VirtualBox or VMWare.