530 5.7.1 Client was not authenticated

An Exchange server has been set up on Windows server 2008R2. It is OK to send out email after completion, but an error is returned from the external address:

The mail transmission process is interrupted, usually due to an internal system failure of the service provider of the recipient (* * @ * .com).

Host. Com said: 530 5.7.1 Client was not authenticated (in reply to MAIL FROM command)

This error is related to the access permission of SMTP, that is, the "Anonymous users" group is not checked, and the setting is as follows:

After "Server configuration"-> "Hub Transport"-> "accept Connector"-> "Default server"-> permission Group-> "Anonymous user" check.

Or:

Open Exchange Management Shell and enter the following command:

Command Set-ReceiveConnector "Default"-permissiongroups: "ExchangeUsers,ExchangeServers,ExchangeLegacyServers,AnonymousUsers"

Or

Command Set-ReceiveConnector-Identity "Default"-PermissionsGroup "AnonymousUsers"