Can you share what error you're getting? 

Also, is UAC turned off on the Host? Are you using the correct username format of: hostname\username? 

I get the error, "invalid credentials" and "this is not a hyper V server"

UAC is turned off from registry.. And I restarted the server. 

Yes username format is correct. I used both host name and IP still no success 

Did you remove the server from Veeam prior to removing it from the domain?  If it is still there try removing it from Veeam then adding again. I think there is something leftover in the DB that might cause issues.  You more than likely should open a support case.

@Chris.Childerhose no, I only removed it from the the domain. Did not want to remove it from the Veeam server itself so all backups do not start afresh. Might try that later though. 

But you need to remove it as it will still be associated to the domain possibly causing the issue you are seeing.  Let us know if that works once you do.

Well, I have a server on another environment that underwent the same process but It was added fine without taking it out of the Veeam Server.

But I will try that out and let you know the outcome.

@Danyang007 - Another option is to call Veeam Support to see if there’s something specific you can do we haven’t suggested yet.

Another thought I have - since the Host is now off the Domain, did you add it’s hostname/IP to the hosts file on your Veeam Server for name resolution? Worth a shot if you haven’t already.... Altho the error you're getting suggests you are seeing the Host, but just having an issue with authentication. I seem to recall a Veeam KB or something in the User Guide about local SID/admin accounts...

I also suggest you try adding all the servers of the HyperV cluster in the hosts file.

IP nebios name

IP FQDN

Thank you for the suggestions guys,

Will try adding te IP to the Host file of the veeam server

Will also try removing and re-adding the server to the Veeam application .

Will let you guys know the outcome of this steps . 

Hopefully one of these works and you will not be required to contact Support.  Best of luck.

Hello Guys, tried every idea that was suggested, unfortunately issue was not fixed.

I saw somewhere where the issue was related to DistributedCOM and had to be fixed with a windows update of the Veeam Server (Server 2016). This did not fix the issue because a particular update kept failing to install, so I had to download the update manually and install.

KB5036899 Security Update was the fix.

https://catalog.s.download.windowsupdate.com/c/msdownload/update/software/secu/2024/04/windows10.0-kb5036899-x64_55391ef83ffb9a029d2489da756a3fb562d4e600.msu

After installing it on my Veeam Server and restarting, I was able to onboard my Hyper V servers with local admin credentials.

So thank you everyone for all the suggestions and assistance. I am really grateful.

Glad to hear you were able to fix the issue with that KB patch.

Thank you for sharing what worked for you @Danyang007