Offener Brief an HostGator-Kunden

The HostGator block has been lifted. Thanks to all the MX Guarddog customers who reached out to HostGator on our behalf. With your support HostGator's senior staff did remove the block and reach out to us directly. See update #7 below for more information.

On March 24, 2016 @ 22:10 GMT HostGator started rejecting your incoming mail. It does not matter if the message is spam, it does not matter if you have spam protection enabled or disabled on your hosting account, they flat out refuse to accept any mail being delivered to your mailbox from IP address which is one of the IP addresses used by MX Guarddog.

MX Guarddog quickly reacted by routing mail to your inbox through an alternate IP address. However, some mail is still being rejected by HostGator.

Our attempts to deliver your important email will result in the following rejection message by HostGator.

550-"JunkMail rejected - []:53439 is in an RBL on, see Blocked - see blocked"

This error is indicating that HostGator has placed our IP address on a blocklist, which is operated by HostGator and used internally (they share this blocklist with other hosting companies owned by their parent company Endurance International Group). This is not a public blocklist and we have been unable to locate any way to apply to have the block lifted.

Accidents happen and their systems may have accidently added our IP address to their private blocklist. MX Guarddog is an anti-spam solution, we do not send spam and no spam is originating from our network.

All attempts to contact HostGator over the past 17 days have been ignored, or we have been told that because we are not a customer ourselves they will not assist us. HostGator's croc has very tough skin and we are simply not having any luck getting through to them - we need your help.

To ensure that MX Guarddog is able to deliver your mail, we request all HostGator customers to please contact HostGator by email, telephone +1 866-964-2867, live chat or any means you can and express your concern over the blockage of your incoming mail.

Got a Twitter account? Send out a tweet, using #hostgator and hopefully someone at HostGator who has the power to fix this will hear you.

If you are a HostGator customer, please direct HostGator to this page by providing them with this URL:

We would love to hear from someone at HostGator who is in a position to discuss this blockage and determine how it can be lifted. How can we prevent future blocks against us so HostGator customers can choose to use MX Guarddog's email security service without fear that HostGator will decide to block their customers from receiving mail? HostGator can contact us directly at to resolve the issue.


Thanks to those customers who value MX Guarddog's service and have already reached out to HostGator.

Update #1

An attempt to contact HostGator via their live chat, with customer support representative Jeremy S. he stated "we are currently aware of a Blocklisting issue and are working to resolve this company wide". Unfortunately we do not believe this to be true, the blocklisting they are doing is directly against MX Guarddog's IP address.

Update #2

Another HostGator customer received the following answer from William Normandin, a Triage Administrator at HostGator about the block. It was suggested that MX Guarddog should stop sending so much mail, and we should request delisting - unfortunately we see no way to apply to have the block lifted from this private blocklist.

Update #3

We have now received a 3rd reply from another HostGator tech, thanks to queries by our shared customers. Tech Brandy H. has stated that it is not HostGator who is blocking the IP - it is someone else (she did not say who).

Our research shows the RBL websitewelcome is in fact controlled by HostGator. The ownership of the domain is hidden, but HostGator actually makes mention of the domain on their website, in addition when you connect to an email server managed by HostGator the welcome message states it is

Logic would dictate that if connecting to a server that claims to be and the rejection message says our IP is blocklisted by then HostGator knows something about the blocklist.

We have checked 95 blocklists using MX Toolbox and we appear on none of them - it is only the HostGator controlled blocklist that is rejecting mail.

We have not yet been contacted by anyone from HostGator.

Update #4

HostGator has not reached out to us, but our shared customers continue to contact the HostGator support channels and are getting their attention. HostGator support agent Jacob I. is requesting proof of the rejection in the form of headers from an undeliverable message. We can do better than that, here is a screenshot of a manual connection test so they can see the entire communication channel leading up to the rejection notice and disconnection by HostGator.

Update #5

One of our shared customers opened a helpdesk ticket with HostGator on March 25th regarding the delivery issues. HostGator has not been taking any action on it. Today that customer has followed up with HostGator. Here are some direct quotes from customer support agent Suede Y.

"Sadly for the issue with MX Guard Dog we do have their servers on our black list due to excessive spamming in the past. In this case the mail was rejected because their sending server was blocked. In this case we will not remove this block as it is on our RBL which is a fairly conservative and if they want to be removed from it they need to curtail their spam."

"Sadly we have removed them in the past and have gotten issues right away from spam so we no longer unblock MX Guarddog."

There is clearly some misunderstanding here, MX Guarddog is an anti-spam service. We are not a bulk mailer, we don't send spam and customers can't relay mail out from our network. We protect inbound mail from spam and viruses, forwarding clean processed mail to customers servers (some of which are HostGator customers). We have been in control of the IP Address since August 2014. We can't speak to what spam was sent on that IP before we took ownership of it, but we can be certain there has not been spam sent on that IP since we took it over.

It is unfortunate that someone from HostGator has not reached out to us (we are available 24/7 at, with so many of our shared customers contacting them regarding this issue. All we can do is request someone from HostGator to contact us, show us this spam that support agent Suede Y. is suggesting we are sending. If there is spam originating from our network we can take care of it, but we have no records to indicate we are the source of any spam.

Update #6

We have received some additional information regarding the block from HostGator support rep Hisako P.

"Do you have a bounce back message including the full email headers please?"

"It's our policy that we will not investigate any potential blocklists found, because of faulty flags that can happen with places like So the way we can confirm whether or not issues are actually happening from the potential blocklist is to obtain a bounceback with full email headers that would enable us to better deduce or confirm the cause of the issues with email."

"The best solution would be to look into Google Business Apps. While still using your domain, you would also be using Google's mail service rather than the shared mail gateways that we provide."

"An alternative would be looking into a VPS or Dedicated solution. This too would take you off the shared mail gateways we provide and give your domain(s) lone access to send email from the IPs provided. Once again, I do apologize for any inconvenience this may cause you."

While support agent Hisako P. is very polite, he seems to think the issue is a problem with sending mail and is suggesting the customer move to Google hosted mail or upgrade to a dedicated server.

HostGator claims to have more than 9,000,000 domains hosted with them. So the fact that their block against MX Guarddog is impacting only a very small number of their customers does not seem to matter. MX Guardodg is large enough that the volume of mail we deliver gets us noticed and blocklisted, but small enough that the HostGator users who are impacted don't matter.

The only mail MX Guarddog is delivering is mail specifically delivered to HostGator customers who use MX Guarddog's email security service. Unless a domain is both a customer of HostGator and MX Guarddog, MX Guarddog would never be making an email delivery attempt. By blocking MX Guarddog and providing no way for HostGator customers to whitelist our IP addresses they are essentially saying that any customer who uses MX Guarddog is not permitted to receive any email.

Update #7

HostGator has a very large network and a massive number of customers. Our issue with the IP block was a bit unusual and HostGator's 1st level tech support staff did not quite know how to deal with it. Fortunatly with enouogh MX Guarddog customers contacting them the problem was escalated to more senior level support and the block against MX Guarddog's IP address was lifted. Email destined for HostGator customers should once again be flowing without any issues at this time.

We were contacted directly by Ryan E. who is a supervisor at HostGator. He confirmed that the block has been lifted and explained a bit about how their internal blocklist works and how we got on it. I will not document that here as we don't need real spammers gathering that information for themselves!

"... we regret that we were not able to contact your staff directly about this issue and could have saved your customers (and ours) some frustration ... we'll implement training and policies as appropriate to make it easier to communicate problems with us."

"... feel free to reach out to us again via chat or phone call anytime if there is ever a problem with your customers being able to send mail to our network ..."

Thanks to everyone for their efforts in getting this issue resolved, glad to see email flowing again to the HostGator network.

Updated 2016/04/09