I've setup a test solution to experiment with Ldap Authentication.
I've followed the documentation and looked into this as well, then I've setup my MyLdapAuthenticationSource
in the Core project along with the package Abp.Zero.Ldap
and set Configuration.Modules.ZeroLdap().UseUserPrincipalNameAsUserName = true;
When I tried to login I receive Invalid Username or Password message.
Additionally, I setup a default .NET 5 Microsoft solution to verify that I'm able to connect to the Active Directory directly and it worked as expected.