SMTP Error 550 indicates that the receiving mail server has rejected an email message entirely. This usually occurs due to spam filtering rules, invalid recipient details, or strict mail server policies.
Unlike temporary errors, SMTP Error 550 usually requires corrective action before email delivery can be successful. This guide explains how to identify and resolve message rejection issues when using Domains.co.za email services.
TABLE OF CONTENTS
How to Resolve SMTP Error 550
1. Review the bounce-back message and confirm SMTP Error 550 is listed.
2. Verify that the recipient email address exists and has been spelled correctly.
3. Remove suspicious links, attachments, or excessive formatting from the message.
4. Confirm that SPF and DKIM are enabled for your domain.
5. Login to your Domains.co.za account.
6. From your dashboard, open the Manage Services menu and select the hosting service linked to the domain you wish to manage.
7. Click Manage next to the relevant domain, then select Login to cPanel.
8. Open Email Deliverability and repair authentication records if necessary.
9. Retry sending the email after adjusting.
10. Ask the recipient to whitelist your email address or domain.
11. Contact Domains.co.za support if the rejection continues.
Additional Information
- SMTP Error 550 represents a permanent rejection rather than a temporary delay.
- Spam filters often trigger this error when authentication records are missing or invalid.
- Blacklisted sending IP addresses can cause immediate rejection.
- Sending bulk or unsolicited email increases the likelihood of this error.
- Poor sender reputation affects how receiving servers treat messages.
- Reviewing full email headers can help identify the reasons for rejection.
- Maintaining proper authentication improves long-term delivery success.
Login to Domains.co.za Account
1. Go to the Domains.co.za website Account Login page.
2. Enter your Email and Password and click the Sign In button.
3. You will see the Domains.co.za Dashboard, displaying the Manage Account menu on the left and your Account Information, Account Overview and Open Support Tickets on the right.
