SMTP Authentication

Select the email authentication mode:

• Anonymous: The default selection. If your Exchange server is within your firewall, you would typically use this authentication mode.
• Basic: If you select this option, you must supply a user name and password in the SMTP User and SMTP Password fields. The SMTP Password field can hold up to 250 characters.
• NTLM: Non-standard authentication. This mode provides tighter security into your SMTP server.
• OAuth 2.0: Select this option to use OAuth 2.0 authentication for SMTP using Microsoft Exchange. If you select this option, you must specify the Service, Tenant and Client ID, and Client Secret.

For detailed information about email authentication, see the Microsoft documentation.