Changing a single server from FRS to DFS

I have been trying tio sort out this problem for a while as I want to add a new server as a DC and turn off the old DC. Every time I tried I found that I had an error so I went searching for an article to sort out the FRS to DFS upgrade. read pages, and pages, watched vidoes. I then found this simple guide so I put the link in here.

It works

https://www.rebeladmin.com/2015/04/step-by-step-guide-for-upgrading-sysvol-replication-to-dfsr-distributed-file-system-replication/?unapproved=35024&moderation-hash=06a497a050bf665663e796ee55771549#comment-35024

IF AFTER SETGLOBALSTATE 2 YOU GET A SERVER WHICHG WONT UPDATE BECAUSE IT IS MISSING OR NON EXISTAND THEN DELETE IT IN AD USERS AND COMPUTERS. YOU DONT HAVE TO DO THE SUBTREE.