With a Windows Server 2016 Standard server set up as a web server for hosting a handful of websites, is there any reason to keep Windows Defender running?
The server has limited resources and the more services that can be disabled the better. Windows Defender seems to be one of those built-in Windows Services that my not necessarily be needed for a basic web server?
No if you got an antivirus running, as anyhow most antivirus will desactivate by themselve windows defender on their install
nb; The lack of ressources for the server must not be an excuse to make it unsecure.
Windows Defender is the updated version of the forefront antivirus. It was a light antivirus but it's not as good as https://www.malwarebytes.com/
So if you ask me, I always recommend the use of this tool prior to any vendor antivirus. It really makes antivirus obsolete (premium version only). you can try it 30 days.