How do I run a 32 bit program on windows 7 64bit OS

I have a 32 bit program that used to run fine on windows XP (32bit) however no matter what I do to run it through the compatibility system I keep getting the same message ask supplier for 64 bit program, the manual ( windows 7) tells me there is a compatibility for doing just this but it won't work, anyone have any help on this would be much appreciated?

What is the application? What is the exact message in the manual? There is no universal procedure that will allow all 32 bit programs to run in a 64 bit OS.

Most programs run right away in x64 systems, but few might have problems.
If your program uses drivers (a rare occurrence) then you absolutely need a native 64 bits version.
THe most likely cause, however, it's that the program is actually a 16 bits one, whose compatibility completely has been removed in 64 bits Windows.