How to make an extremely old app run on 64bit Windows?

I have a very old application designed for Windows 3.1. I have been able to use this application on Windows 7, however, that was Windows 7 32bit. Now I have since re-installed Windows to 64bit, and this application does not work, saying it's incompatible. I have tried running the application (and its other side-applications) in Windows '95 mode, but still the same message.

How can I run this old app on 64bit Windows?

For the record, the application is a game called "Sim Tower"

Answer

You can install and run it, with Dosbox and the Windows 3 for dosbox.

1. Download Dosbox


2. Download Windows 3 for dosbox
   Attention: You have to have a license for Windows 3, that you are allowed to use it. The download is only there, because you can't find an official-download from microsoft itself.


3. Unzip both archives in one new folder.


4. Add a new folder to this folder and name it, Simtower.


5. Now add all the files from Sim Tower to this folder.


6. Start dosbox.


7. Now execute the following command at the dosbox-commandline:
   

   
   

   mount c c:/your/path/where/you/have/dosbox/installed

   
   

   
   


8. Change to the c drive by simply writing: c:in the dosbox-commandline.


9. Launch windows.bat inside the dosbox.


10. Windows 3 will now boot.


11. Open the folder Main->File Manager.


12. Now there should be a Simtower-folder.


13. Open it and launch the setup.exe.


14. Now just restart Windows 3, and you can run Simtower.

Of course, this will work with other Windows 3-programs as well.

Source of Windows 3 for dosbox.