Outlook has been redirected to server autodiscover

Recently, a user reported a relatively unpopular error. When you log in to outlook using V River Crab PN, the mailbox is sent and received normally. After disconnecting V River Crab PN, you cannot connect to the server. The screenshot of the error report is as follows:

Online check no related posts, directly see, check the IIS directory of the SSL configuration and HTTP redirection configuration, there is no problem, and thought about whether recently to do anything to the server.

Finally, I thought that the public network address of the server had been changed before, so nslookup checked the parsing of the extranet autodiscover and found that the parsed extranet address was the invalid IP, so we knew what was going on.

Log in to the supplier's DNS parsing console, change the A record of Autodiscover to the extranet IP of the current server, retest, and solve the problem.

Such problems generally do not occur during the initial installation of the Exchange environment, but are set up in accordance with the standard steps. Only in the medium-term use, when the public network IP address of the Exchange is changed for some reason, the administrator step will cause negligence.