As usual with Microsoft, it seems that have come up with a “better” idea for how to install the Remote Server Administration Tools for Windows 10 versions later than the October 2018 Update.

In the search, enter “Manage optional features” and click “Add a feature.”

And then the brilliant engineers at Microsoft, thought it would be so much better if we had install each component one at a time. So, pick and chose at your will. Click an RSAT option and then click Install. At least, they will queue. To get a status, just go back to the previous screen.

You need to reboot once you have all the features installed.

To install (or reinstall) the ActiveDirectory module, I think the only feature required it the “RSAT: Active Directory Domain Services and Lightweight Directory Services Tools”. It was not in “RSAT: Server Manager.”

Then, from a administrator Powershell windows, install the module:
PS> Install-Module ActiveDirectory

I had to re-install RSAT and the ActiveDirectory module after update to version 1909.

I have yet to come across the powershell equivalent to just install the tools. I will update this if I find it.

This is the best way to install the powershell ActiveDirectory module, because it actually works:

$JGZSession = New-PSSession -ComputerName domaincontroller
Export-PSsession -Session $JGZSession -Module ActiveDirectory -OutputModule RSATADModule
Remove-PSSession -Session $JGZSession
Import-Module RSATADModule