About Active Directory replication account settings
Auto Config replication account settings are under Optimization > Active Directory: Auto Config.
Active Directory automatic configuration settings
Admin User
Specifies the replication username. Maximum length is 20 characters. These special characters are not supported: / \ [ ] : ; | = , + * ? < > @ “. You can only add one replication user per domain.
Password
Specifies the user account password.
Replication Domain/Realm
Selects the replication domain in which you want to make the replication user a trusted member from the drop-down list. You must preconfigure the replication domain. If none exists, the list displays None.
Domain Controller
Specifies the hosts that provide user login service in the domain, separated by commas. Typically with Active Directory Service domains, the system automatically retrieves the domain controller name when given a domain name.