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Hotmail / Outlook Blacklist: How To Remove your IP from it

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    The Outlook blacklist is a powerful tool used by companies and individuals to protect their inboxes from malicious emails. However, many business owners and web users don’t fully understand how the Outloook blacklist works or why it should be taken seriously. 

    In this blog post, we’ll take a look at exactly what the Outlook blacklist does, how it affects your email deliveries, and why you need to pay close attention to this crucial security tool. 

    By the end of this blog post, you will have all of the information that you need to properly configure your system in order to stay off the Hotmail /Outlook Blacklist!

    What is Hotmail /Outlook blacklist?

    Outlook, formerly known as Hotmail, is an email service provided by Microsoft. It is integrated into the broader Microsoft email ecosystem, which includes various features and tools to enhance email management and security.

    Within the Microsoft email ecosystem, there is a feature called “blacklisting” or “blocking” that allows users to prevent specific email addresses or domains from sending messages to their Outlook inbox. By adding an email address or domain to the blacklist, any emails originating from those sources will be automatically filtered into the spam or junk folder or completely blocked from reaching the recipient’s inbox.

    This blacklist feature helps users to manage unwanted or malicious emails effectively, protecting them from spam, phishing attempts, and other forms of unwanted communication.

    It’s worth noting that Outlook’s blacklisting feature is just one component of the overall email management and security measures provided by Microsoft. Other features include spam filtering, malware scanning, phishing detection, and encryption options to ensure the safety and privacy of user emails.

    Microsoft maintains two distinct blacklists for different email platforms: Exchange Online Protection (EOP) and Outlook.com.

    1. Exchange Online Protection (EOP).

    EOP is Microsoft’s cloud-based email filtering service designed for businesses and organizations using Microsoft Exchange Server or Office 365. It includes a comprehensive set of features to protect against spam, malware, and other email-based threats. EOP maintains a blacklist known as the Exchange Online Protection IP Blocklist, which contains IP addresses that are identified as sources of spam or malicious activity. Emails originating from these blacklisted IP addresses are either blocked or marked as spam.

    2. Outlook.com.

    Outlook.com is Microsoft’s consumer-oriented email service available to individual users. It incorporates various security measures to protect users from unwanted emails and phishing attempts. Outlook.com maintains a separate blacklist called the SmartScreen Filter, which helps identify and block potentially harmful or spammy email addresses and domains. The SmartScreen Filter analyzes various factors such as the sender’s reputation, content analysis, and user feedback to determine whether an email should be delivered to the inbox, redirected to the spam folder, or blocked entirely.

    Why Hotmail can Blacklist your IP?

    In some cases, Hotmail may blacklist an IP address to prevent spam and malicious emails from entering its network.

    There are various reasons why Hotmail may blacklist your IP address. 

    ✅ One of the primary reasons is when your IP address is associated with suspicious activity such as sending a large number of emails in quick succession or compromising user accounts. In such cases, Hotmail may block your IP address to prevent any further suspicious activity and protect its users.

    ✅ Another reason why Hotmail may blacklist your IP address is when your emails contain suspicious or spammy content. For instance, if your emails include high volumes of certain keywords, inappropriate attachments, or links to suspicious websites, Hotmail’s filtering system may flag your emails and prevent them from reaching their intended recipients.

    ✅ Furthermore, it’s important to note that Hotmail’s blacklist is not permanent and generally only lasts for a few days or weeks. However, if the suspicious activity continues, the blacklist may be extended, which could result in severe consequences for your email marketing efforts.

    In conclusion, maintaining a good reputation with Hotmail is crucial for any email marketer who wants to reach a large number of people through email. To avoid being blacklisted by Hotmail, it is essential to maintain high standards of email practices, ensure that your emails contain relevant and valuable information, and avoid sending unsolicited emails to Hotmail users.

    How to Check if you're on the Outlook blacklist?

    1. Use an online blacklist checker.

    The best and most informative at the moment is the email deliverability test from Warmy. It is absolutely free. Just go to the page Email deliverability test and follow the 3 steps to check if your domain and IP are blacklisted.  In this test, you will see all the most famous domain and IP blacklists, except for this error in SPF, DKIM, DMARC settings, and placement of your emails.

    IP blacklist

    2. Monitor your email deliverability.

    If you notice a significant decrease in your email deliverability to Outlook recipients or consistently find your emails landing in their spam or junk folders, it could be an indication that you are blacklisted. Keep track of the email delivery performance to Outlook addresses and check if there are any consistent issues.

    3. Check your bounce messages.

    When your emails are rejected or blocked by an email provider like Outlook, you may receive bounce messages or error codes explaining the reason. Examine these bounce messages for any indications that your email address or domain is on their blacklist.

    Example of a 550 Hotmail bounce code:

    A 550 Hotmail bounce code typically indicates a permanent failure in email delivery. Here’s an example of a 550 bounce code message from Hotmail:

    “550 SC-001 (SNT004-MC2F35) Unfortunately, messages from [sender’s IP address] weren’t sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors.”

    In this example, the bounce code is “550,” indicating a permanent failure. The additional information within the parentheses provides more details about the error, including the server or data center code (SNT004-MC2F35) and the specific reason for the bounce (part of sender’s IP address on block list S3150). The bounce message suggests contacting the Internet service provider (ISP) and referring them to the provided troubleshooting link for further assistance.

    Complete list of Hotmail/Outlook SMTP bounce codes.

    Here is a list of common SMTP bounce codes associated with Hotmail/Outlook:

    ◾ 421 RP-001: The mail server IP connecting to Outlook.com is experiencing a high volume of traffic. Retry sending the email after some time.

    ◾ 421 RP-002: The IP address of the mail server attempting to send to Outlook.com is temporarily blocked due to suspected bulk email or spam.

    ◾ 550 SC-001: The mail server’s IP address is on the Outlook.com blocklist. Contact the Internet service provider (ISP) or refer them to the troubleshooting link for resolution.

    ◾ 550 SC-002: The sender’s IP address is on a blocklist used by Outlook.com due to being identified as a source of spam.

    ◾ 550 SC-003: The mail server’s IP address is on the Outlook.com blocklist due to being identified as an open proxy.

    ◾ 550 DY-001: The mail server IP is sending an excessive amount of emails, triggering the Outlook.com rate limit policy.

    ◾ 550 DY-002: The sender’s email address is blocked by Outlook.com due to being identified as a source of spam or suspicious activity.

    ◾ 550 OU-001: The email server IP address is on the Outlook.com blocklist due to a history of generating poor reputation email traffic.

    ◾ 550 OU-002: The sender’s email address or domain is blocked by Outlook.com due to a history of generating poor reputation email traffic.

    ◾ 550 OU-003: The email server’s IP address is blocked due to a compromised account or unauthorized access.

    4. Contact Outlook support.

    If you suspect you are on the Outlook blacklist but are unable to find concrete evidence, you can reach out to Outlook support for assistance. Contact their customer support or visit their official website to find resources or contact channels to report issues related to blacklisting.

    How to request removal from the Hotmail/Outlook blacklist

    1. Identify the reason for blacklisting.

    Determine the specific reason why your email address or domain was blacklisted by Hotmail/Outlook. This could be due to spam complaints, sending unsolicited emails, having a compromised account, or other violations of their email policies.

    2. Resolve the underlying issue.

    Take necessary actions to address and resolve the underlying issue that led to your blacklisting. For example, if your account was compromised, change your password, enable two-factor authentication, and run security scans on your devices to ensure they are free from malware. If you were sending unsolicited emails, review your email marketing practices and ensure compliance with anti-spam regulations.

    3. Improve your email sending practices.

    Review and enhance your email sending practices to ensure you maintain a good sender reputation. This includes obtaining proper permission from recipients, avoiding spammy content and excessive mass emailing, and regularly monitoring and addressing bounce rates, complaints, and unsubscribes.

    4. Get Removed from Microsoft Blacklist.

    If you find your IP address still on Outlook’s blacklist, take the next step to contact your ISP requesting removal from being on any blacklist. Your ISP should have information on how to go about doing this. 

    Once removed from any previous blacklists, it is essential to complete the Microsoft Sender Information Form on their website to remove your IP from Microsoft’s blacklist. 

    Provide all your server’s IP address, name, server type, website URL, contact email, timezone, email domain you’re using to send emails and any relevant error codes received.

    🔥 Stop getting blacklisted with Warmy.io! Take action now to protect your email reputation and ensure your messages reach the inbox. Say goodbye to spam folders and missed opportunities. Don’t wait any longer, safeguard your email deliverability with Warmy.io today!

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