Not able to create DFS namespace in a completely new forest

Not able to create DFS namespace in a completely new forest

OS: Windoes server 2016
DFL: 2003
FFL: 2003
DFS role on member server 
creating very first namespace server - Errors in : The object identifier does not represent a valid object

Have already tried clearing the container in ADSIedit,
Clearing Registry keys
HKLM\SOFTWARE\Microsoft\DfsHost
HKLM\SYSTEM\CurrentControlSet\Services\DfsDriver\LocalVolumes
HKLM\SOFTWARE\Microsoft\Dfs\Roots\Domain\xxx
HKLM\SYSTEM\CurrentControlSet\serivces\LanmanServer\Shares

and tried re-creating but it fails. 

What could be stopping it for namespace creation?? any ideas, two days already spent on this .

and another thing is why do sometimes I keep getting RPC server unavailabe?? Windows Firewall is off.

Would really appreciate the suggestions.