Assuming you've actually installed the software on the Windows 7 computer (Windows programs cannot be moved/copied by just copying their folders), then most likely it is a 16-bit program that you are trying to run on Windows 7 64-bit. I'm assuming because you did not provide any details. If my assumptions are correct, then probably your only choice is to run the salon scheduling software in a virtual machine, a copy of Windows XP that runs on Windows 7.
If you have Windows 7 Pro or Ultimate, then you can run their copy of Windows XP in XP Mode. If you only have Windows 7 Home Premium then you'll have to run another free virtual machine emulator, such as Virtual Box.