AX fail to send mail by SMTP , COM error code 0x80040211, 0x8004020f

The error code is as below:

"Method 'send' in COM object of class 'CDO.Message' returned error code 0x8004020E (<unknown>) which means: <unknown>."

How To Fix This:

If you get any errors related to SMTP transport then the cause is either SMTP settings (relay address/port, relay authentication parameters, etc), or email settings (for instance, invalid/prohibited to/from/cc/bcc addresses), but not in the SysMailer class.
Steps to fix this:
first, make sure the SMTP server is working, and your account and password are right.
If you are using your own company's SMTP, one way to check the SMTP is using telnet, please refer to this

Then you need to check you setup Email parameters properly in your AX.

Please pay attention to 'UserName', sometimes it is a matter whether you input the full name or only user name.

e.g. if you are using gmail, and your account is test@gmail.com. you may face error 0x80040211 if you input 'test@gmail.com' as 'UserName', you must input 'test' as the 'UserName'.

But most of the time, you may input 'test@gmail.com'.
COM error 0x8004020f: The server rejected one or more recipient addresses
This is happening because your SmtpMail.SmtpServer is rejecting addresses.

Make sure all email addresses specified at MailMessage.To, MailMessage.Cc, MailMessage.Bcc and MailMessage.From are valid email addresses.

Make sure you have permissions to relay through the server.

Make sure the MailMessage.From has permissions to relay through the server.

Please check you email especially when you use a address filter!