Windows Defender was uninstalled after installing F-Secure Server Security 15.10 on Windows Server 2016.
On ESS manual (SS should be the same as well) describes below.
After installing the product on Windows Server 2016 or newer, you need to explicitly disable or uninstall Windows Defender.
Does this mean that Windows Defender is not automatically uninstalled even though "Switch off Windows Defender during installation" is enabled?
Is this expected behavior?
There are other servers which Windows Defender was not uninstalled but it was just disabled. What is the difference?
Actually Server Security uninstalls Windows Defender from the server.
But it will be enabled back upon our product uninstallation.
In case, it's necessary for Windows Defender to get back without uninstalling our product, they can run this command in powershell with admin rights.
We don't actually log the output of Windows Defender disabling attempts - there could be different reasons why Windows Defender can't be uninstalled in some cases, e.g., GPO settings on the server.
powershell Install-WindowsFeature -Name Windows-Defender
Customer can, for example, try the command
by themselves on the affected server, and see if it works.
powershell Uninstall-WindowsFeature -Name Windows-Defender
Article no: 000034029