I have the PAServer running on my MacBook without password.
From my Windows/Delphi I then try setup the connection. I enter IP address and empty password. However, when testing the connection, I get error:
TDBXError: Remote error: Authentication manager rejected user credientials. This may due to invalid combination of DS user name and password
The question has been answered (Thanks!)
As a sidenote: I am not sure how this could be closed as not a "real question"? :) Documentation, as I read it at least, did not state a password was required. Using a password solved the problem.