I've just downloaded the httrack_x64-3.49.2.exe version from
<http://download.httrack.com/cserv.php3?File=httrack_x64.exe> and Windows
Defender has flagged it as a virus.

The reason I visited the forum is to see if anyone else was reporting it.

It was flagged as:

"Trojan:Win32/Vigorf.A"

The windows defender version I have is...
"Anti-malware client version:4.12.17007.18022
Engine version: 1.1.14600.4
Anti-virus definition: 1.263.81.0
Anti-spyware definition: 1.263.81.0
Network inspection system engine version: 2.1.14202.0
Network inspection system definition version: 118.2.0.0"