windows 8 - Force a program to run on x86?

I'm using Windows 8.1 x64, and I'm trying a legacy app.

I get an error message complaining that the program is not compatible with x64.

Is there a way to force a program to run on 32-bit mode on a 64-bit system?

Here are some screenshots, that might shed a light on what type of program this is:

I run the program pointed to by the arrow, and the message show up one after the other (when clicking OK):

Answer

Since you have provided so little information, I am going to hazard a guess that the program your are running is not actually 32 bit, but 16 bit.

Look at the title bar of the first screenshot. It says "Unsupported 16-Bit Application"

32 bit Windows applications should run under 64 bit Windows. 16 bit applications will not.

I believe if you really have to run this application, you can get around this by running 16 bit application in a 32 bit virtual machine.