SAM 2009.10.2 is a legacy version that was relased in October, 2009. This is the first version to have a Mac version in addition to a Windows version. This version works with .zsam files, so the current version cannot open files created with this legacy version.
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.