1) Double check that test emails didn’t go to spam folder – sometimes that happens.

2) Try using simple php mail() delivery method first.

3) Make sure you you’re using all the right ports/usernames/passwords – please double check with your provider.

4) Make sure you have set Sender Email and Sender Name (image below) – if you will be using SMTP authentication, these 2 parameters HAVE to be the same as the name/email you’ll use to authenticate to SMTP.   If above won’t help – it means that there is some incompatibility with mailing software we use and your server and it would require advanced troubleshooting