Cox Communications is a United States telecommunications provider with over 6 million customers.
According to Cox, as of August 15, 2019, they do not offer the ability for new and existing Cox Internet customers to create new Cox email accounts. The inability to add new email accounts should cause the number of Cox subscribers on your email list to decline over time as customers change internet service providers and use other email services.
Infrastructure
Region |
North America: United States |
Domains |
Cox.net; Cox.com |
Connection and throughput |
The volume of messages allowed by Cox servers may vary depending on your sending reputation and other factors. |
Complaint feedback loop (FBL) application |
|
Postmaster site |
Deliverability best practices and troubleshooting support
- Use opt-in permission methods for all subscribers. Do not purchase email lists or engage in list harvesting from third-party websites.
- Monitor Cox's SMTP response codes when encountering delivery issues. The SMTP response codes provide additional information to help you troubleshoot.
- Configure all IPs with valid reverse DNS (PTR) records.
- Ensure your sending domain has a valid MX record or A record.
- Authenticate all email with SPF and DKIM.
- Have a list hygiene strategy in place to remove or suppress unknown and unengaged users from your email list. Email sent to too many unknown users may be blocked.
- Look up and delist all IPs and domains from the following blocklists, including any third party domains. Be sure to fix the cause of any blocklistings prior to submitting a delisting request or listings will recur.
- Spamhaus
- Validity RPBL
- Invaluement
- Cloudmark CSI: See Cox's error codes to determine if listed on the Cloudmark CSI blocklist.
- SURBL
Mediation
- Contact Cox for assistance with delivery issues.