How to resolve this error message on my email setting

Welcome to the forum @CDN,

You can refer to the following guides for a step-by-step instructions on how to setup your email in Manager:

Thank you @Ealfardan for your response. I have followed the instructions on both articles but I’m still getting the same error message. I have been on this for hours.

Have you create an app password to be solely used for Manager?


Also, are you using an email alias?

Yes I have

Are you using an alias email address?

No, I am not. I’m working with my main email address.

I have researched this error 5.3.0 and came up with this:

Message Not Delivered: Unknown Issue With The Receiving System

The message could not be delivered because of an unknown problem with one or more of the recipients’ email systems.

Double check that the recipient’s email address is correct. Wait a few minutes, then try sending the message again.
If necessary, contact the recipient(s) another way (e.g., phone or text message) to confirm their email address.

5.3.0: Official Definition

[RFC3463] (Standards Track) from the The Internet Engineering Task Force (IETF) definition for codes that start with 5.X.X:

A permanent failure is one which is not likely to be resolved by resending the message in the current form. Some change to the message or the destination must be made for successful delivery.

[RFC3463] (Standards Track) from the The Internet Engineering Task Force (IETF) definition for codes that end with X.3.0:

The destination system exists and normally accepts mail, but something about the system has caused the generation of this DSN.

Source: Email bounces for everyone -

The good news is that this means that the error is occurring on the email server side and not Manager side.

This also means that your options for fixing this are limited:

  1. Ensure that the email address you provided is correct
  2. Try again at a later time.