Recipient Blacklisting or Rejection

Important Note: This article is specifically for email that is not being delivered and generating delivery errors from your mail that specify which blacklist rejected the mail. If you are not experiencing both of these conditions, the following articles may be more helpful:

If you believe you are being blacklisted, but you are not receiving error messages, please skip to the following section:

This article covers the following topics to help address and better understand blacklisting:


How to Resolve Blacklisting

Many different aspects of your email may be blacklisted, including but not limited to: the source IP address, your domain name, your email content, or the server IP address. HostGator may only directly assist with blacklisting If you are receiving errors that indicate that your server is being blacklisted.

Note: If you are not receiving mail delivery errors that specify blacklisting as the cause, please read How to Check for Blacklisting.

The following article will assist with understanding error messages in case the message does not clearly identify that your server IP address is blacklisted:

If the error messages you are receiving indicate that the server is being blacklisted, you must provide full headers from the error message in order for HostGator to assist directly. The following article will assist you with viewing your full headers in webmail:

The following page provides directions for retrieving full headers from a large number of third party email programs:

After retrieving the full headers of your error message, please contact us for assistance.

Note: We can only fix a blacklisting issue if the block is against the entire server. If the block is specifically against your email address, domain, local IP address, or content, then the receiver is blocking your emails purposefully and you will need to directly contact the blocking agency to get the blacklisting removed.

What is Blacklisting?

When an email is marked as spam, the email is reviewed for blacklisting. If the email is determined to be spam, then the server address, email client's IP, domain, or even the email address that sent the spam may be placed on a list known as a blacklist.

Some email servers subscribe to one or more blacklists to better filter out messages with a poor reputation, which may generate mail delivery errors.


How to Check for Blacklisting

Checking for blacklisting can be difficult and looking for it can prevent troubleshooting more relevant issues. If you are not receiving a delivery error which explicitly states you are being blacklisted, you likely have another issue that is faster and easier to resolve.

Popular webtools, such as mxtoolbox.com, should not be used to troubleshoot blacklisting. These tools frequently include a blacklist report that commonly include some or all of the following errors:

  • Stale Results: A false positive from a blacklist that has already been delisted.
  • Irrelevant Results: Blacklists that will not prevent your mail from being successfully delivered. Click here for more information.
  • Inaccurate Results: Frequently these tools use your domain's IP address, which is the site your website is hosted at and not the IP used to send your email.
  • Incomplete Results: These tools will not identify spam blocks from major email providers, such as AOL, Google, Yahoo, or ISPs such as AT&T.

Given these issues with the core functionality of the blacklist checks these tools performs, HostGator strongly recommends disregarding these results unless you are receiving mail delivery errors that specify blacklisting.

If you are receiving mail delivery errors that specify blacklisting, please read How to Resolve Blacklisting, otherwise, please check the following articles for any errors you are experiencing:


Blacklists HostGator Will Not Address

There are some black lists that do not prevent mail from being delivered. In order to effectively stop mail, a blacklist must be subscribed to by an email server.

We maintain a list of blacklists which do not prevent mail delivery, and from which no mail delivery errors should result. However, almost all of these blacklists can and frequently are reported by third party blacklist checking tools.

HostGator will not address any blacklisting issue without a delivery error message (including Full Headers) specifically referencing them as the source of rejection:


Receiving Mail From Blacklisted Sources

Our Shared and Reseller servers keep a list in sync with companies that monitor IP addresses that are sending spam. If a sender's IP address is on this list, then our servers will block email from the IP until the sender's IP is no longer on the list.

If the sender can have the IP address removed from the blacklist, you will be able to receive email from them normally.

Our list is updated every four hours which will allow for mail to continue normal delivery if the sender has their IP address removed from the blacklist.

If you wish to receive email from a domain that is on a blacklist you will need to get a VPS or Dedicated server. For more information, see this article: