How are SYSINFO.nOSMajor and SYSINFO.nOSMinor derived? Are these coming from setup.exe looking at some registry keys or probes from the Windows API? If I were to run an installer on Windows 7 would it register these values properly? One of my fellow devs is suggesting we bypass these built-ins and rely on looking up registry values manually. What is IS2009 doing to populate these SYSINFO values and how resilient is it to working with the next generation or two of Windows?
These values are retrieved directly from GetVersionEx. This should be fine in a pure InstallScript project, however Windows 7 will be shimming this in MSI Custom Actions to report Windows Vista. In a Basic or InstallScript MSI project, it is suggested that you reference the VersionNT property instead.
