I'm having issues playing games like Duke Nukem 3D and Hexen. [Both Demo Versions] I try to play a game through one of the games applications and I get an error message: This system does not support fullscreen mode. Choose 'Close' to terminate the application. (On the top of this window, It's called 16 bit MS-DOS Subsystem) Help Would Be Very Much Appreciated!
Keep in mind that Duke Nukem 3D and Hexen were both games that were released back in 1996.
If you have a current VAIO computer system, chances are you are running into a compatibility issue between the Windows operating system and the games. I highly doubt that there are any updates or patches for either of those two games to make them work 100% properly on modern computers.
There may be hacks or workarounds to make them work better, so your best best is to go on the Internet and search for things like 'duke nukem 3d windows 7' or 'hexen windows 7,' and see what comes up.