Failed when validating user through authentication service
When creating the end-to-end authentication process by which a user (for example) will be authenticated, there are things to consider such as where the authentication process will be initiated, which authentication module(s) will be used in the process, and what, if any, post authentication steps will be implemented.The authentication type (where the authentication process will be initiated) is specified by appending an appropriate parameter to the login URL, or through the authentication API.ail Secure (all versions), M Guardian (all versions)The "authentication" settings in NMS (the authentication portion of a "mail route" policy) serves 2 purposes,1.to validate a user's credentials when they log in to access the quarantine.2.This way we don't run into the same problems we had when validating users via SMTP, we don't populate multiple user objects in NMS for each of the backend user's valid email addresses, we know they all belong to the same user.
Before the SMTP transaction can proceed, in order for NMS to respond to the sending server's "rcpt to" command, NMS needs to determine if the recipient exists or not (sometimes referred to as "lookahead"), how the user validation is performed depends on the type of authentication you have configured in NMS., The NMS will connect to the SMTP server defined in your authentication settings which we often refer to as the "backend" server (if you use Group Wise this would be your GWIA, if you use Exchange this would be the Hub Transport) only this time NMS is the "sending" server, it will initiate an SMTP conversation like we see above until it reaches a point where it can "rcpt to" the same recipient.
Most enterprise class email systems (Exchange, Group Wise, etc.) store user information in a directory in the form of user objects, a user object has various attributes such as a username, first name and last name, etc.