How To Remove Your IP from Yahoo Blacklist – Yahoo Blacklist Checker

How to Remove Your IP Address from the Yahoo Blacklist

Is Yahoo blocking your emails? Your sending IP address may be blacklisted by Yahoo! Mail.

Yahoo users, Gmail users, and Hotmail users are often victims of spoofing and phishing. Thus, email service providers developed filters and blacklists to protect their users from spammers sending spam.

If you recently noticed your email marketing metrics dropping, your IP address may have been blacklisted.

This article will show you why Yahoo may have blacklisted you and how to remove your IP address from the Yahoo Blacklist.

Why Yahoo’s Blocking Emails

Yahoo does not disclose specific information about its email filtering requirements. But like most mailbox providers, Yahoo checks the sender’s IP reputation to decide if an email should be delivered and where it should be placed: Inbox or Spam.

Factors that Impact Sender Reputation:

  • IPs listed in Spamhaus and other spam databases
  • Bounce rates
  • Complaint rates
  • Spam trap hits
  • Changes in email volume
  • User engagement

How to Get Blacklisted

There are many ways your IP address can end up on the Yahoo block list. Blacklisting issues can be caused by:

  • Compromised user accounts used to send spam.
  • Emailing mailing lists, newsletters, forums, and blogs in bulk (even if they are opt-in).
  • Bulk emailing subscribers from a purchased email list.
  • Bulk forwarding spam emails to Yahoo users.

The last one is often overlooked. If you forward an email to a Yahoo address and you then mark it as spam, Yahoo will penalize your server.

This problem is often seen with shared hosting servers. Some users can just forward all of their emails to Yahoo. These are often junk accounts that receive tons of spam messages.

Yahoo Blacklist IP Check

Unlike public IP blacklists, there is no way to quickly perform a Yahoo blacklist check.

Run an email deliverability test with GlockApps to see if Yahoo’s blocking your emails.

Simply look up the results for Yahoo emails and see if Yahoo blocked your domain. If Yahoo rejected your message, the results under “Delivered to:” will display as “Undelivered.”

Yahoo blacklist checker

Yahoo Error Codes

Typically, when Yahoo blocks your public IP address, you may receive a bounce message with the following error message:

421 4.7.0 [TS01] Messages from <> temporarily deferred due to user complaints
<> ;see


553 5.7.1 [BL21] Connections will not be accepted from,
	because the ip is in Spamhaus's list; 

Other Yahoo SMTP Error Codes

SMTP ErrorDiagnostic Error MessageDescription
421421 Message temporarily deferred – [numeric code]The message content contained objectionable content, we’re seeing unusual traffic from your servers, or emails from your mail server are generating complaints from Yahoo Mail users.
421421 4.7.0 [TS01] Messages from x.x.x.x temporarily deferred due to user complaints – 4.16.55We’re seeing unusual traffic patterns from your server.
421421 4.7.0 [TS02] Messages from x.x.x.x temporarily deferred due to user complaints – 4.16.55We’re seeing unusual traffic patterns from your server or your mailings are generating complaints from Yahoo Mail users.
421421 4.7.1 [TS03] Messages from x.x.x.x permanently deferred. Retrying will NOT succeedWe’re seeing a high volume of e-mails from your server that are indicative of unsolicited mailings.
451451 Resources temporarily not available – Please try again later [numeric code]This error indicates that our servers were busy and temporarily unable to process your transaction at the time of connection.
451451 VS1-IP Excessive unknown recipients – possible Open Relay (#4.1.8)Your mail server is configured as an open relay or proxy.
451451 VS1-MF Excessive unknown recipients – possible Open Relay (#4.4.5)The senders MAIL FROM address has been sending to excessive bouncing accounts (non-active, don’t exist). Review your mailing lists, and remove any addresses that generate bounces.
553553 5.7.1 [BLXX] Connections not accepted from IP addresses on Spamhaus PBLThe sending IP is listed on a Spamhaus blacklist. You can check your status on Spamhaus’ site
554554 Message not allowed – [numeric code]Your emails have become deprioritized due to the message content triggering our filters. We ask that you review the email’s header and message content for potentially objectionable content.
554Delivery error: dd This user doesn’t have a account (****** [-5] – [BODY]The Yahoo account that you’re trying to send to doesn’t exist. We recommend that you contact the recipient directly to confirm their correct email address.
554554 5.7.9 Message not accepted for policy reasonsYour message wasn’t delivered because Yahoo was unable to verify that it came from a legitimate email sender.

How to Remove IP from Yahoo Blacklist

Blocklists intended to block spam can drastically affect your email marketing efforts. Once Google, Hotmail, or any other ISP flags your IP address, you’re more likely to have deliverability issues and difficulty reaching the inbox with another service provider.

If you performed a Yahoo blacklist check and found that your domain’s IP address was on the Yahoo blacklist, you have to fix the issue before you try to request removal.

Start by analyzing your mail servers to make sure your DNS settings are properly configured:

  • Reverse DNS resolves to a hostname.
  • SPF is valid.
  • DKIM is working properly.
  • Your hostname has an A record.

DNS is one of the most critical elements in email marketing and delivery. Always test your server and fix DNS issues before you send emails as they could be the reason why your emails are being rejected.

If you found the problem, wait a bit. In many cases, the block on your mail address is removed in less than 48 hours. If it’s not, fix the original issue and take additional steps to get off the Yahoo blacklist.

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1. Request Removal from Spamhaus Blacklist

Yahoo uses Spamhaus, a public real-time blacklist. Make sure your IP is not listed there. If it is, you need to request removal from Spamhaus before you contact Yahoo.

You might find that once your IP is removed from Spamhaus, your emails may start flowing to Yahoo emails again.

2. Complete Yahoo Sender Form

yahoo blacklist

No matter how many emails you send, you can open a support ticket with Yahoo.

Though some fields are optional, we recommend providing as much information as possible, especially, in the “Additional information” field.

Use 2-3 sentences to explain what you did to fix the reason why your emails are being rejected. Keep it short and technical. The Yahoo postmaster staff receives hundreds of requests daily, so being short and to the point helps accelerate the Yahoo blacklist removal process.

Visit the Yahoo postmaster page to find more information about Yahoo’s best email standards and deliverability troubleshooting tips.


Yahoo Blacklist Check

Learn More about Blacklist Removal:

IP Blacklist Removal – How To Fix a Blacklisted IP Address
Why are my Emails Blocked by Gmail?
How to Remove Your IP Address from Gmail’s Blacklist
How to Remove Your IP Address from the Hotmail/Outlook’s Blacklist


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Julia Gulevich is an email marketing expert and customer support professional at Geminds LLC with more than 15 years of experience. Author of numerous blog posts, publications, and articles about email marketing and deliverability.