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Contact Form
If you are having problems with mail delivery to Cox and the Error Codes section did not contain sufficient information to resolve the problem, use this form to contact us for assistance. Due to the technical nature of the requested information, this form should be submitted by an email administrator or other technical contact that is familiar with, and can obtain, the following information.

Note: If you are visiting this page after receiving an error code from a Cox-owned mail server, following the instructions associated with your error code under the Error Codes section may result in a quicker solution to your issue.

*First Name:

*Last Name:

*Email address:

Phone Number:

*Domain Name:

*IP/CIDR Range of outgoing mail servers:

Please select the item that best describes the problem you are experiencing:

Please give a detailed description of the problem you are experiencing, including the date and time when the problem began and what corrective action has been taken to this point.

Please include any mail server logs that show the problems encountered

Why am I being blocked?

The error message that was displayed at the time of the block contains information regarding the reason. . More details about the various error messages can be found in the Error Codes section.

Can I get unblocked?

This depends on the reason for the block. The details of the error you encountered are found in the Error Codes section, which contains information on how to request a block be lifted.

Can I be whitelisted?

Protection of our customers and network is paramount. Therefore, we do not whitelist.

Does Cox offer a Feedback Loop?

Yes. See the Feedback Loop section here.

What are Cox's sending limits?

Cox currently allows up to 5 simultaneous connections per sending IP address, and up to 100 messages per connection. However, regardless of these limits, Cox may throttle your sending ability based on your sender reputation. Cox's sending limits and policies are subject to change at any time. Cox will update this website when changes are made.

How do I report abuse?

Please find instructions on how to report abuse here.

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