I have a similar problem but the solution to disable authentication is not appropriate. In my case, the Veeam Monitor Client is installed on a laptop that is not part of any domain. I do have credentials within the same domain as the Veeam Monitor Server, so I just need to know how to have the client use those credentials when connecting to the server. (eg. similar to mapping a network share).
Is there some way to configure the client with alternate "domain\user" credentials to use when connecting to the server?