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"


2 Answers 2


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.

  • Excellent (except no install / setup, it runs stand-alone) Oct 19, 2013 at 21:26
  • @JerryDodge Thx, good to know. I've edited my answer.
    – Christian
    Oct 19, 2013 at 21:28

If it is a Windows 3.1 application, it is a 16bit application, not a 32bit one. Windows 7 64bit does no longer have a 16bit sub-system. So you can not run this app directly. You can install XP-Mode to run Windows XP on top of Windows 7 and then run your app in that XP virtual machine.

  • 2
    Please note that the free "Windows XP Mode" is only available for Windows 7 Professional and higher.
    – Rik
    Oct 19, 2013 at 21:16
  • Otherwise, another option would be Oracle Virtual Box, or equivalent virtual machine software - running any other version of Windows which supports this. Oct 19, 2013 at 21:17
  • @JerryDodge Yep, but then you'll need to buy a Windows XP license. There is a possibility to use DOSBox but then Windows 3.11 (also with license?) has to be installed on top of that because this game needs Windows.
    – Rik
    Oct 19, 2013 at 21:20
  • @Rik Yup, I edited my comment to point that out (although the license should be obvious :-) ) Oct 19, 2013 at 21:21
  • 1
    @Rik windows 7 Pro and higher, but not Windows 8 of any flavour. :) Oct 19, 2013 at 21:22

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