How to verify office 365 email address using API

Question

How can I verify and make sure that the email address I input is correct/active before I send an email to it? Do we have any REST API that I can use? I am looking to verify email addresses with domains other than my own email address domain.

Thank you in advance.

Answer 1

You cannot, there is no way for Office 365 (or any system) to validate external addresses. Only after sending a message and observing the server reply you can determine whether an external address is valid or no.