Send email outlook not working

I made a simple program that sends an email to an account and writes “sent” in the message box after, when i run it, i get the message “sent” and in the outlook application the email is on the “sent itens”, but i never receive it, after i while i receive a email from “admin” saying that an error occured, it only happens with the university email, can someone tell why?

are you able to send same email to same destination using your outlook client?