Strange my mailer never worked. Logins are correct. Tried several SMTP servers office 365 and different ones. So credentials ARE 100% correct. In DEBUG i only get back
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Thats it. If a make a mistake and put wrong password then it shows me same. Except I put SSL checkbox, then I get a message. Is it possible to test mailer locally before going live with external SMTP server?
If there is an error returned by your server, you should be able to see it if the output/throw errors options in your action steps are enabled.
If the server action runs without error - ie. status 200, but the email is still not being sent, then there is something that happens on your mail server that prevents this, so please check server logs.