An error occurred sending the test email Alert Eror What do you think could be the reason?
Try removing the quotes around the email address in Recipients.
Unfortunately, it did not happen
Can you try unchecking the TLS check-box?
If you’re on Linux you can also check on /var/log/mail.log for errors. (I expect you’ll see something like “did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA-v4”.)