Website SMTP Settings for Office365
To use SMTP from your Office365 account, you’ll want to use the following SMTP info:
Server: smtp.office365.com
Port: 587
Encryption: STARTTLS or TLS
SMTP Authentication: The username & password for your Office365 mailbox.
Note that you may need to enable Authenticated SMTP for your mailbox so that address can send email via SMTP.
Log into your Microsoft 365 admin center. Go to Users > Active users, select the user, and click Mail in the flyout that appears. Then in the Email apps section, click Manage email apps.
See this Microsoft article if you need help with that setting.
If you have 2FA enabled on your Office365 account and experience an authenticator error despite enabling the Authenticated SMTP option, you may need to create an app password. See this article for guidance on creating an app password for your account.