I have the original Sim City Unlimited 3000 disc, and it was installed fine on my computer, and I was able to play it, but suddenly I am unable to play it. First it said I needed authorization, then I uninstalled it, thinking I could reinstall it, and now it won't even install. HELP! If it has something to do with the Windows update, how can that be fixed? I am totally screwed, and never able to play the game again?!
Your game was released while WindowsNT and Windows98 were current OSes, and the Win 10 compatibility mode for XP is apparently faulty, but is as far back as they even tried to go with the newest MS Windows version. I don't think that either Windows 8.0 or 8.1 would handle your old 1999 game.
If you have the space for an extra PC setup, your local thrift shop has old PCs running the older Windows versions, that you can buy for very low prices.
Have you checked with Good old Games to see which old Simcity they are offering now? They tweak it to run with modern OSes. It's probably the Simcity 2000 version, though. (Edited later: Good old Games has both Simcity 4 and Simcity 2000, and both should be ready to run.)
Have you read the reply? It was edited to add some information, if you want to recheck.
