Oldest game you have installed on your current computer?

And also how much work does it take to get to actually work.

I have Petz 4 which came out in 1999, and while a few features don't work (it actually had a voice recognition ability, but that is hard to get working these days), it generally plays fine. 

I also have Knights of The Old Republic (2003), which was fine on my previous computer (Windows 10), but has weird graphical issues on Windows 11. 

And the absolute oldest is Zoombinis, bought through Steam, but originally out in 1996 (and I probably first played it in that year or the year after). Weird educational kids game, with lots of logic puzzles.