How to Run an Older Program in Windows XP and Vista
Originally, this page was written for Windows XP alone but Windows Vista has a similar capability. That is described below.
Many older computer programs may not run correctly if you just click on the program's executable file in Windows XP; this is particularly true of older game programs. There can be many reasons why. Perhaps the program uses DOS calls that XP does not know about. Perhaps there are graphic hardware considerations. Perhaps...who knows.
Indeed, some older DOS-based programs, in order to speed up the display, wrote directly to the computer's hardware. These, Windows XP will not allow to run at all. In order to run these you will have to find a computer with an older operating system or a good emulator or virtual computer (see below).
For those in between, there is some hope in using Windows XP's Compatibility Mode.
Open Windows Explorer and navigate to where the program is located. Then...
Basically, this action creates a PIF file that Windows uses to determine options to use to run the program in compatibility mode instead of native Windows 32-bit mode. Hopefully, this will allow the program to run.
If you are concerned with running older DOS programs you may need an emulator. FILExt has not tested this as these emulators are evolving. They may or may not work in Windows Vista.
There is another developing option for running older DOS programs under newer Windows operating systems: the DOSBox project. DOSBox emulates an Intel x86 PC. It is a developing option because the project is still refining the code. But, you can find it at its Sourceforge home...
An MS-DOS emulator called FreeDOS has finally been released in version 1.0 (Sept 2006). This OS can be downloaded as an ISO file that can be burned to a CD and used as a boot disc so the computer is then running DOS. While you will likely not be able to correctly access your hard disk if it's an NTFS formatted disk this is another option for running older software on a new computer. You can find it at its Sourceforge home...
If these suggestions don't work for you, you are back to finding a computer with an older operating system.