I’m looking at the Microsoft article for Operating System Property Values and it seems that both Windows Server 2008 R2 and Windows 7 have a VersionNT value of 601. I see in the comments on the article that you should use MsiNTProductType to differentiate the two.
So if I wanted to only allow server 2008 R2 installations (and not Windows 7), then would this be the correct condition:
MsiNTProductType > 1 AND VersionNT = 601
This would allow me any Windows 2008 R2 PC that is a domain controller or a server (Which Windows 7 is not?)
I just built a MSI installer with that launch condition and that will indeed work just fine.