1. Go to 'Tools'

2. Select 'Email accounts'

3. Click on 'View and change existing email accounts' then click 'Next'

4. Select 'mail.domain.com' and click on 'Change'

5. Under 'Server Information', change the Outgoing mail server (SMTP) to smtp.dnshostmaster.net

6. Click on 'More Settings'

7. Go to 'Outgoing Server' tab, make sure 'My outgoing server (SMTP) requires authentication' is checked

8. Check on 'Log on using', enter User Name: smtp@domain.com and the password is provided by us

9. Go to 'Advanced' tab and change the Outgoing server (SMTP) port number from 25 to 587

10. Click 'OK' and 'Next' to finish