Upgrade Domain Controller From Server 2016 to Server 2019

In this post we are are going to upgrade Domain Controller from “Server 2016” to “Server 2019”, this is also known as in-place Upgrade. There are few Pre-requisites. You will need to run adprep /forestprep and adprep /domainprep manually. Adprep /forestprep needs to be run only once in the forest. Adprep /domainprep needs to be run once in each domain in which you have domain controllers that you are upgrading to Windows Server 2016.