3.1.3 Initialization

The client SHOULD send an Autodiscover command request ([MS-ASCMD] section to the server to determine the correct server URL to use for all subsequent commands.

After determining the correct server URL, the client SHOULD send an HTTP OPTIONS command to the server, as specified in section 2.2.3. The client SHOULD<5> use the most recent version (the greatest numbered version) of the protocol that is supported by the client and server.