Windows platform:
· Windows Vista, or Windows 98, ME, 2000 or XP with .NET 1.1 framework or higher (if the .NET framework is not installed, the installation wizard of Photomatix Pro will invite you to download it from Microsoft's website).
from http://www.hdrsoft.com/support/faq_photomatix.html#requirement
You should read the system requirements before installing any software to save surprises.