So you have Windows 7  but you either cant find the Windows driver for your Sound Card or your trusted old Windows XP program fails to work under your new OS. If so there is a way to allow you to run a program using the compatibility mode of your previous (working) Windows version.

Steps :

1. Right click on the application (.exe) and select Properties.
2. With Properties go to the Compatibility Tab and choose your Windows Version and select Run program as administrator
3. Once done click OK and then double click to run the program as normal.

Not only can this be useful for running legacy programs but you can also use this for running driver . exe files.
In the case of my Sound Card drivers which I only could find XP drivers for I did the following :

1. Downloaded the XP drivers (.exe file)
2. Extracted the .exe file using WinRar.
3. Located the .exe file within the extracted files and choose Windows XP SP3 as the compatibility mode option.
4. Ran the .exe and installed the drivers as per normal.