How do I set up Multi Factor Authentication (MFA) with Office 365?

ISSUE:

 I have been experiencing intermittent failures when sending SMTP emails from PDF-eXPLODE via Office 365. I was advised that the possible reason for this was my old version of PDF-eXPLODE had an outdated TLS component. So I updated my PDF-eXPLODE version which now includes TLS V1.2/1.3, but the problem of email failure still continues intermittently. I then noticed these lines in a recent SMTP email log in PDF-eXPLODE.

SmtpCmdResp: 535 5.7.139 Authentication unsuccessful, user password has expired. [CH0PR03CA0283.namprd03.prod.outlook.com]
smtpStatusCode: 535
--readSmtpResponse
SMTP authentication failed after sending password.
office365_tips:
Your office365 account might be requiring MFA (multi-factor authentication).

How do I set up Multi-Factor Authentification (MFA) as well as create and deploy an App Password in the PDF-eXPLODE SMTP?

ANSWER:

How to create App Password (Multi-Factor Authentication) for Office 365 SMTP Server

Introduction

To turn on Multi-Factor Authentication (MFA) you should read the article at this link https://docs.microsoft.com/en-us/microsoft-365/admin/security-and-compliance/set-up-multi-factor-authentication?view=o365-worldwide

Once you have MFA enabled for your MS Exchange Online mailbox in Office365 or Microsoft365, then you can’t use your main account password in PDF-eXPLODE SMTP settings to authenticate the Office365 emails to go. You will need to create a separate  App Password  and use it in the SMTP settings of PDF-eXPLODE. Generally, when sending an email via PDF-eXPLODE using Office 365, your regular Username and password should suffice.  if the email fails with a similar error message as indicated above (in ISSUE), then most likely you need to use an App Password. This is also a message you are likely to get in your email log:

An error occured sending the message, Error:80048011
Unexpected AUTH LOGIN password response, Last Response: 535 5.7.3 Authentication unsuccessful [BLAPR03CA0069.namprd03.prod.outlook.com]

SMTP Authentication

Make sure SMTP Authentication is enabled for your online email account:  https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission .

To Create App Password

1. Sign into Office 365.

2. Choose  Settings > Office 365 .

3. Choose  Security & Privacy > Additional Security Verification . You’ll only see this option if your admin has set up multi-factor authentication for your organization. If you don’t see this option,  contact your Office 365 admin and tell them to turn on multi-factor authentication.

4. After selecting the option as shown above, choose  Update my Phone Numbers Used for Account Security . You should see the following screen:

5. At the top of the page, choose  App Passwords .

6. Choose  Create  to get an app password.

7. If prompted, type a name for your app password, like "PDFeXPLODE" and click  Next .

8. Click on   copy password to clipboard  button.

9. Open Notepad and paste ([CTRL]+V) this App Password and a description like:  Today's date/ Office365 App Password. Then click FILE/SAVE and Save this Notepad note to PDF-eXPLODE folder with a name like O365-App-Password.txt

10. Now open email settings in PDF-eXPLODE and use this password for SMTP connection parameters instead of your main account password.

Office365 SMTP Server Settings for PDF-eXPLODE

The settings below should work for everyone with an Office 365 or Microsoft 365 plan that has Exchange Online. Use these settings in PDF-eXPLODE E-mail Connection settings  

• SMTP Server address: smtp.office365.com
• SMTP Port number: 587
• Security Protocol: StartTLS
• Authentication:  Login
• Username: (your Office 365 email address) (myemail@mycompany.com)
• Password: (your Office 365 password) ==> APP PASSWORD (16 characters)