Under Client Access server (Web Services, %BRAND_OUTLOOK_SHORT% Anywhere, and Autodiscover) , select %BRAND_EXCHANGE_ONLINE_SHORT% ...

Under Client Access server (Web Services, %BRAND_OUTLOOK_SHORT% Anywhere, and Autodiscover), select %BRAND_EXCHANGE_ONLINE_SHORT% Web Services is enabled. Then select %BRAND_OUTLOOK_SHORT% Anywhere is enabled and specify the external FQDN of the %BRAND_EXCHANGE_ONLINE_SHORT% 2010 SP3 server that has the Client Access server role installed. Then select Autodiscover is used on the Internet, select Long URL, and specify the Autodiscover URL you want to use for this server. For example, autodiscover.contoso.com.