Yes I use an Microsoft “passive” directory.
But the auth dn will be product depend.
For example for an Microsoft ldap use “%s”.
Please enable the debug log of gmvd to be sure, that you not run into an SSL problem with the ldap server.
As far as I know the debug output will only enabled on level 128.
Oh as I see, the forum software will break some formats.
So her the login dn for MS again “DOMAIN\%s”
In an windows “world” it will be enough to use the domain name as the server name, because all domain controllers will be resolved to it. In your case it looks like none of the domain controller can be reached.
You can check the connection via telnet or or openssl for start tls.