Smtp works in old security but not in new

I have a ctrl app which uses the old style sc_mail_send (hard-coded params) and it works perfectly. Using the exact same credentials to use “forgot password” in the new security system (sc_loginsettings) I get Connection Cannot be Established. I have tried various connection strings to different mail servers and they all work when put in directly and the same do NOT work when put in the sec_loginsettings in new security. What am I missing here?