What do you mean by “ERROR: Failed to connect to server: Connection timed out or SMTP Error: Could not connect to SMTP host.”?

If you get a ‘Connection Timed out’ error when sending an email via our SMTP relay, it means that you are using an SMTP port that is blocked.
By default, we recommend using port 25 (no encryption) when sending emails via our SMTP relay. However, some ISPs may block port 25.
If this is the case, try using port 587(TLS Encryption) or 2525(no encryption). You can find this port information on your SMTP Settings page.

Related Resources

A complete guide to choosing the right SMTP port.