Microsoft's backward compatibility efforts have been extraordinary, but many things simply stopped working. For example, if you try to run a DOS 16-bit program in a 64-bit Windows environment, you'll get an error, but if the Windows build is 32-bit and we let NTVDM do its thing, the story is different… even for those old viruses that sowed absolute terror in our hearts. The question is: How effective are they these days?
For obvious reasons, anyone attempting to reproduce this experiment should do it on a separate computer disconnected from the local network. The person behind the channel Nostalgia Nerd did exactly that by acquiring a PC based on a Ryzen 5 3400G with 8 GB of RAM in single channel, and a solid-state drive. Installing 32-bit Windows 10 and keeping that single channel are very bad ideas (especially if we plan to use the integrated video), but the environment is more than adequate for playing with old viruses.
The fury of classic viruses, today
Now, the famous Malware Museum has dozens of examples if you want to “enjoy” them from the browser, but they were completely neutralized. The plan is to install DOS malware on Windows 10 without modifications, so that if they still have some damage capability, they can deploy it without restrictions. That's when the “classic” portal VX Heaven comes in, torn down and restored multiple times. Copies of its malware database continue to float on the Web, and with a basic search it's easy to find them.
The viruses that specialized in infecting .COM files seem to work… with some details. For example, Ambulance shows its animation, but the .COM infection gets caught in a loop, creating copies of itself until the original .COM of a few bytes easily grows to 20 or 30 megabytes. The disturbing Casino works by throwing a couple of errors, and not finding a FAT to destroy, it doesn't do much. In contrast, DOSBox presents a more “friendly” space. LSD makes multiple copies in the directory occupying 1,600 bytes, but it also managed to infect larger .EXE files.
https://old.neoteo.com/descargas-gratuitas-oldergeeks/The last step of the experiment is to run them all at the same time (6,745 samples, with duplicates removed)… with a beautiful disaster as a result. Among the viruses infecting each other, .COM files drastically increasing in size, and the natural loss of resources under such a task, the computer ended up on its knees, with corrupted video, connectivity problems, and strange files on the Windows desktop. In summary, if you decide to do this at home, remember that the definitive solution is Lieutenant Ripley's diplomacy.
