The outlook connection server of Apple MAC has changed the name of the Intranet and Internet. Recently, when I was working on a project, I found that the MAC Outlook anywhere domain name on the internet is normal, however, the connection server over the Intranet will become the CAS server, which leads to a problem that the connection fails as soon as the user reaches the Intranet. The customer's architecture is four Exchange servers, two Mailbox role servers, and two HUB/CAS server roles. Cas array is established and associated with MAILBOX, and high availability of CAS is achieved through dns robin. Www.2cto.com read the MAC version of OUTLOOK and found that the Exchange connection is through the EWS interface to connect to the Exchange server itself. The reason is found, so the solution is very easy. Solution: you only need to unify the EWS directory locations on the two CAS servers. You can use the following command to achieve this: get-clientaccessserver | set-webservicevirtualdirectory-internalurl "CAS array EWS directory" allows customers to reconnect and solve the problem! By fogyisland2000