The Client Access services now proxy connection requests to whatever Mailbox server is hosting the active Mailbox database for the mailbox being connected to.

Primary AND Secondary datacenter RPC Client Access namespacesД®xchange Server 2019 reduces the number of required namespaces from five down to two because Exchange 2019 does not require RPC Client Access namespaces.

Primary AND Secondary Outlook Web App failback namespaces.

Primary AND Secondary datacenter IP namespaces.

In earlier versions of Exchange (E2K10), there were numerous namespace requirements for Autodiscover that need to be met in order to provide site resilience. When a client that uses Exchange Web Services launches the first time, it configures itself using the Autodiscover service. The URL used will depend on whether the Autodiscover service is configured on a separate site or not.

youremaildomain/autodiscover/autodiscover.xml.

The Autodiscover service URL in Exchange 2019 will be either of the values below:

SCP URLs contain Autodiscover URLs for Autodiscover endpoints. SCP pointers contain information that points to specific LDAP servers that are then used to locate Autodiscover SCP objects in the userвЂ™s Active Directory domain. There are two types of SCP objects for the Autodiscover service that Exchange publishes. It provides an easy way for domain-joined mail clients to look up Autodiscover servers. The SCP object locates the Autodiscover server or endpoint thatвЂ™s appropriate for the user trying to connect. The SCP object points to the Exchange server and provides additional Autodiscover information to clients trying to connect to Exchange. The SCP object in AD stores the authoritative URLs for the Autodiscover service and provides them to domain-joined computers.

When the Autodiscover virtual directory is created, an SCP object is also created in Active Directory. The user can simply provide a username and password, and Outlook does the rest. It allows Outlook to automatically discover the necessary Exchange mailbox settings so that end-users donвЂ™t have to remember technical things such as server names, ports, and protocols. This is the Client Access services web site that clients connect to. Essentially, what preparation of the AD forest and domain does is it adds Exchange attributes and Exchange information to the Active Directory schema.Дuring installation, Exchange 2019 automatically creates a virtual directory called Autodiscover in IIS on the server. Before installing Exchange 2019 in an AD forest, the AD forest and any domains within the forest that will contain Exchange users must first be prepared. Information about user mailboxes, as well as configuration information for the Exchange organization, is stored in Active Directory. The Outlook client can then connect to Exchange using only the user name and password. The Client Access services that run on the Mailbox server provide authentication services as well as proxy services for internal client connection as well as clients connecting externally. Active Directory then stores the authoritative URLs and provides them to domain-joined computers. When Exchange 2019 is installed, it creates a virtual directory called Autodiscover under the default web site in Internet Information Services (IIS). As such, the mailbox server also provides Autodiscover services. The mailbox server now provides Client Access services. Autodiscover also supports multiforest configurations as well.ДЄlthough previous versions of Exchange offered Autodiscover services through the Client Access Server, beginning with Exchange 2016, and continued with Exchange 2019, there is no longer a separate Client Access Server. When configured correctly, Autodiscover can be used by clients to connect to Exchange 2019 from inside or outside of corporate firewalls.

With that said, Autodiscover can also provide information to clients that connect using other protocols. Clients that connect via Exchange Web Services (or EWS) typically connect to the EWS endpoint URL via Autodiscover. The Autodiscover service in Exchange 2019 makes email setup for end users easier by minimizing the number of steps that a user must take to configure the client.

Outlook 2019 metered connection warning