You are misinformed. Microsoft even supports Vista, not to mention 7. [1] In addition, if XP support deadline extensions are anything to go by, then these Windows 7 end-of-support dates will get moved several times until they stick. Beyond that, Windows 7 remains by far the most popular Windows version, exceeding the combined market share of Windows 8, Windows 8.1 & Windows 10. [2][3]

Unrelated to market share & OS updates, there's the technical question. There aren't many Win32 APIs which are present in Windows 8, but not Windows 7. Thus it's not that likely that Windows 7 wouldn't be supported by a Win32 app (which this is), unless they go out of their way to make it so.

[1] http://windows.microsoft.com/en-us/windows/lifecycle

[2] http://www.w3schools.com/browsers/browsers_os.asp

[3] https://www.netmarketshare.com/operating-system-market-share...

> You are misinformed.

According to Wikipedia I'm not: https://en.wikipedia.org/wiki/Windows_7#Support_lifecycle

"Mainstream support for 7 ended on January 13, 2015."

I think it's reasonable that businesses don't support an OS version beyond the OS's provider's own "mainstream support".

> Thus it's not that likely that Windows 7 wouldn't be supported by a Win32 app (which this is), unless they go out of their way to make it so.

Possibly, but listing support on their website means they support it, and why should they do that if, again, Microsoft itself does not?

Literally 5 words later:

Extended support will end on January 14, 2020

Ending mainstream support is Microsoft's way of saying: from now on you'll only get security fixes and no new features. Windows 7 support hasn't been dropped in any other way.

But windows 7 is still support by microsoft. Extended support goes until 2020.

Because they bill it for use at work and the overwhelming majority of businesses are using Win7 there.