Your IP address is in our blacklist

You can no longer send e-mails and receive the message '554 Access denied - Under investigation for spam abuse. Contact your email provider for more info'. This problem is caused by spam.

Spam is often sent without your knowledge by:

  • viruses and malware that send spam from your system;
  • an incorrect mail server setting, which allows spammers to misuse your domain name to send e-mails;
  • sending newsletters to several people whose e-mail addresses don't (or no longer) exist and which you forgot to remove from your mailing list;
  • spammers who have obtained your personal data through phishing fraud.

To ensure e-mail traffic runs smoothly for everyone, we block such senders and put them on a “blacklist”. If you end up in our blacklist, you need to take the following measures to prevent further abuse.

Install updates & scan your systems

  1. Install the latest updates of your operating system on all your computers.
  2. Scan your systems for viruses and malware with a good program. For private customers and small companies, we recommend Norton Security, and for large companies, Managed Security Services.
  3. If you think spam was sent from your e-mail addresses or suspect phishing fraud, then immediately change the password of your mailbox(es). Don't forget to update the password in your e-mail program.

Check the settings of your mail server

If you don't have your own mail server, you can skip this step. To check the settings of your mail server, follow these steps:

  1. Send e-mails from your own SMTP (mail)server with DNS resolution and not via relay.proximus.be. For this, configure the name of your mail server in your e-mail program. The outgoing mail server "relay.proximus.be" is exclusively reserved for private customers with specific e-mail standards. It is strictly forbidden to send mailing lists via relay.proximus.be, but you can send them via your own SMTP (mail)server.
  2. Check whether PTR and SPF records have been made for your IP address and domain name.

    PTR record

    A Pointer (PTR) record, also called a "reverse DNS" record, links an IP address with a host name. Professional mail servers worldwide check for the presence of PTR records to make sure that mail servers are authentic and that no home computers infected with malware are sending spam. This way, they can refuse your e-mails if there is no PTR record. Follow the steps below to request a PTR record:

    1. On the website of MX Toolbox, check whether a PTR record exists by entering the fixed external (WAN) IP address of your mail server. "DNS record not found" means that a PTR record does not yet exist for your mail server. If a PTR record exists, you can skip step 2.
    2. If you send e-mails from a Proximus IP address, then you have to request a PTR record from our DNS masters. For this, you need to provide the name of your mail server (e.g. mail.abc.be) and the fixed external (WAN) IP address of your mail server (e.g. Do you send e-mails from a non-Proximus IP address? Contact the owner of the IP address with this data. You can find the owner of the IP address by surfing to WhatIsMyIP on the computer from which you try to send the e-mails.
    SPF record

    A Sender Policy Framework (SPF) record defines which mail server(s) can send e-mails on behalf of your domain. You can refuse or send an alert for e-mails sent from other mail servers with your domain name as sender. Without SPF records, spammers can easily send e-mails from your domain name, which can harm your reputation or result in claims against you. Follow the steps below to request an SPF record:

    1. On the website of MX Toolbox, check whether an SPF record exists by entering your domain name. "DNS record not found" means that no SPF record exists for your domain name. If an SPF record exists, you can skip steps 2 and 3.
    2. We don’t have all the information needed to create an SPF record. That's why you have to create an SPF record yourself with the help of the SPF Wizard.
    3. Contact your domain agent:
      • Can't find the contact details of your domain agent? You can check the contact details of your domain agent on the website of MX Toolbox. On this website, you will also find a link with more explanation about the Sender Policy Framework.
      • Do you have a domain name with us? Copy the DNS entry you created using the SPF Wizard and send it to our DNS masters.
  3. Check the reputation of your IP address and/or domain name and the presence of your mail server on any international blacklists:

    Reputation of your mail server

    Surf to the website of Thalos and enter the fixed external (WAN) IP address of your mail server to check your reputation. This gives you a general overview of your sender reputation. "Good" is recommended and means that your IP address or domain name has a reliable sender reputation. "Neutral" means that the information available is insufficient, and a "Poor" reputation means that you will probably encounter problems delivering e-mail.

    Configuration of your domain name

    Surf to DNS Stuff and enter your domain name in the DNS report field. In case of red or yellow alerts, contact your domain agent.

    Presence on international blacklists

    Surf to the website of MX Toolbox by entering the fixed external (WAN) IP address of your mail server and/or domain name. If you are on an international blacklist, you need to contact the blacklist to be removed from it.

Removing your IP address from our blacklist

Once all the checks have been done, ask to have your IP address removed from our blacklist. If you don't know your IP address, surf to WhatIsMyIP to find your IP address. It is important to carry out all the checks because otherwise there’s a risk that your IP address will be automatically entered into our blacklist again.

We will remove your IP address from our blacklist as quickly as possible. If you have further questions, please contact us.

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