[MAXIUM]

Si usas Outlook 365 (Exchange ) se puede configurar STMP para enviar
https://learn.microsoft.com/en-us/ex...mtp-submission

Enable SMTP AUTH for specific mailboxes

The per-mailbox setting to enable (or disable) SMTP AUTH is available in the Microsoft 365 admin center or Exchange Online PowerShell.
Use the Microsoft 365 admin center to enable or disable SMTP AUTH on specific mailboxes

Open the Microsoft 365 admin center and go to Users > Active users.

Select the user, and in the flyout that appears, select Mail.

In the Email apps section, select Manage email apps.

Verify the Authenticated SMTP setting: unchecked = disabled, checked = enabled.

When you're finished, select Save changes