Assuming you are using the "Lookup Windows version" setting, it unfortunately cannot tell whether it's Windows client or server as both have version "10.0" and there is no additional information available.
Instead, you can use WMI under
Options - Remote WMI and choose
Windows Name, which should tell you the OS installed.
Alternatively, create a new WMI query and use this line to receive the OS name without its installation path:
SELECT Caption FROM Win32_OperatingSystem