Use CDO Send Emails in Excel VBA Not Working - vba

Question

I am trying to send email within Excel VBA. Based on my research on Internet, I enabled Microsoft CDO for Windows 2000 Library and composed my VBA codes as below:
Sub SendCDOMail()
Dim objCDOMsg As Object
Set objCDOMsg = CreateObject("CDO.Message")
'CDO Configuration
With objCDOMsg.Configuration.Fields
'
.Item("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2
'Server port (typically 25, 587)
.Item("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 587
'SMTP server IP or Name
.Item("http://schemas.microsoft.com/cdo/configuration/smtpserver") = "smtp.office365.com"
'Type of authentication, NONE, Basic (Base64 encoded), NTLM
.Item("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1
'SMTP Account User ID
.Item("http://schemas.microsoft.com/cdo/configuration/sendusername") = "xxx#bbbb.com"
'SMTP Account Password
.Item("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "xxxxxxx"
'Use SSL for the connection (False or True)
.Item("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = False
.Update
End With
'CDO Message
objCDOMsg.Subject = "TEST Subject"
objCDOMsg.From = "xx#xx.com"
objCDOMsg.To = "xx#xx.com"
objCDOMsg.TextBody = "TEST Body"
objCDOMsg.Send
End Sub
However, I received the error saying:
The server rejected the sender address. The server response was: 530.5.7.57 SMTP;
Client was not authenticated to send anonymous mail during MAIL FROM
I also tried the same configurations using PowerShell and it worked (smtpserver, username, password, server port...).
I don't know where it might go wrong.

Answer 1

Here it is: https://technet.microsoft.com/en-us/library/mt210446(v=exchg.150).aspx - note that this is in the Office365 section for "How to set up a multifunction device or application to send email using Office 365,", so there may be other things in there for you too.
This indicates that you are connecting to the SMTP client submission endpoint (smtp.office365.com), which can't be used for direct send. For direct send, use the MX endpoint for your Office 365 tenant, which ends with "mail.protection.outlook.com." You can find your MX endpoint by following the steps in Full configuration instructions for direct send.