Login as Administrator
- Go to Settings > System Settings
- Scroll down to 'Outgoing Mail Server Settings'
- Click 'Custom Settings'
- Fill in your SMTP details
- Click 'Update' at the bottom
Common SMTP details can be found here: Here
When you use a custom gateway all emails will come from the SMTP email address specified e.g. email@example.com.
However, the reply-to address will be dynamic email address you've set up in the email template.