Email Marketing ISP Bounce Codes

Yahoo

 

Diagnostic Error Message

Reason

421 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.
421 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. Submit your sending IPs for review.
421 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. Submit your sending IPs for review.
421 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. Submit your sending IPs for review.
451 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.
451 VS1-IP Excessive unknown recipients – possible Open Relay (#4.1.8)Your mail server is configured as an open relay or proxy. Review our guidelines for avoiding deprioritization.
451 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.
553 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.
554 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.
Delivery error: dd This user doesn’t have a yahoo.com account (******@yahoo.com) [-5] – mta1126.mail.gq1.yahoo.com [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.
554 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.

 

 

Hotmail

 

421 RP-001The mail server IP connecting to Outlook.com server has exceeded the rate limit allowed. Reason for rate limitation is related to IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
421 RP-002The mail server IP connecting to Outlook.com server has exceeded the rate limit allowed on this connection. Reason for rate limitation is related to IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
421 RP-003The mail server IP connecting to Outlook.com server has exceeded the connection limit allowed. Reason for limitation is related to IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 SC-001Mail rejected by Outlook.com for policy reasons. Reasons for rejection may be related to content with spam-like characteristics or IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 SC-002Mail rejected by Outlook.com for policy reasons. The mail server IP connecting to Outlook.com has exhibited namespace mining behavior. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 SC-003Mail rejected by Outlook.com for policy reasons. Your IP address appears to be an open proxy/relay. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 SC-004Mail rejected by Outlook.com for policy reasons. A block has been placed against your IP address because we have received complaints concerning mail coming from that IP address. We recommend enrolling in our Junk Email Reporting Program (JMRP), a free program intended to help senders remove unwanted recipients from their email list. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 DY-001Mail rejected by Outlook.com for policy reasons. We generally do not accept email from dynamic IP’s as they are not typically used to deliver unauthenticated SMTP email to an Internet mail server. If you are not an email/network admin please contact your Email/Internet Service Provider for help. http://www.spamhaus.org maintains lists of dynamic and residential IP addresses.
550 DY-002Mail rejected by Outlook.com for policy reasons. The likely cause is a compromised or virus infected server/personal computer. If you are not an email/network admin please contact your Email/Internet Service Provider for help.
550 OU-001Mail rejected by Outlook.com for policy reasons. If you are not an email/network admin please contact your Email/Internet Service Provider for help. For more information about this block and to request removal please go to: http://www.spamhaus.org.
550 OU-002Mail rejected by Outlook.com for policy reasons. Reasons for rejection may be related to content with spam-like characteristics or IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help.

 

Google

 

421, “4.4.5”, Server busy, try again later.
421, “4.7.0”, IP not in whitelist for RCPT domain, closing connection.
421, “4.7.0”, Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been temporarily blocked. Review our Bulk Senders Guidelines.
421, “4.7.0”, Temporary System Problem. Try again later.
421, “4.7.0”, TLS required for RCPT domain, closing connection.
421, “4.7.0”, Try again later, closing connection.
450, “4.2.1” The user you are trying to contact is receiving mail too quickly. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered. For more information, review this article.
450, “4.2.1”, The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered. For more information, review this article.
450, “4.2.1”, Peak SMTP relay limit exceeded for customer. This is a temporary error. For more information on SMTP relay limits, please contact your administrator or review this article.
451, “4.3.0”, Mail server temporarily rejected message.
451, “4.3.0”, Multiple destination domains per transaction is unsupported. Please try again.
451, “4.4.2”, Timeout – closing connection.
451, “4.5.0”, SMTP protocol violation, see RFC 2821.
452, “4.2.2”, The email account that you tried to reach is over quota. Please direct the recipient to this article.
452, “4.5.3”, Domain policy size per transaction exceeded, please try this recipient in a separate transaction.
452, “4.5.3”, Your message has too many recipients. For more information regarding Google’s sending limits, review this article.
454, “4.5.0”, SMTP protocol violation, no commands allowed to pipeline after STARTTLS, see RFC 3207.
454, “4.7.0”, Cannot authenticate due to temporary system problem. Try again later.
454, “5.5.1”, STARTTLS may not be repeated.
501, “5.5.2”, Cannot Decode response.
501, “5.5.4”, HELO/EHLO argument is invalid, please review this article.
502, “5.5.1”, Too many unrecognized commands, goodbye.
502, “5.5.1”, Unimplemented command.
502, “5.5.1”, Unrecognized command.
503, “5.5.1”, “EHLO/HELO first.
503, “5.5.1”, MAIL first.
503, “5.5.1”, RCPT first.
503, “5.7.0”, No identity changes permitted.
504, “5.7.4”, Unrecognized Authentication Type.
530, “5.5.1”, Authentication Required. Learn more here.
530, “5.7.0”, Must issue a STARTTLS command first.
535, “5.5.4”, Optional Argument not permitted for that AUTH mode.
535, “5.7.1”, Application-specific password required. Learn more here.
535, “5.7.1”, Please log in with your web browser and then try again. Learn more here.
535, “5.7.1”, Username and Password not accepted. Learn more here.
550, “5.1.1”, The email account that you tried to reach does not exist. Please try double-checking the recipient’s email address for typos or unnecessary spaces. For more information, review this article.
550, “5.2.1”, The email account that you tried to reach is disabled.
550, “5.2.1”, The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered. For more information, review this article.
550, “5.4.5”, Daily sending quota exceeded. Learn more here.
550, “5.4.5”, Daily SMTP relay limit exceeded for user. For more information on SMTP relay sending limits please contact your administrator or review this article.
550, “5.7.0”, Mail relay denied.
550, “5.7.0”, Mail Sending denied. This error occurs if the sender account is disabled or not registered within your G Suite domain.
550, “5.7.1”, Email quota exceeded.
550, “5.7.1”, Invalid credentials for relay.
550, “5.7.1”, Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been blocked. Review our Bulk Senders Guidelines.
550, “5.7.1”, Our system has detected that this message is likely unsolicited mail. To reduce the amount of spam sent to Gmail, this message has been blocked. For more information, review this article.
550, “5.7.1”, The IP you’re using to send mail is not authorized to send email directly to our servers. Please use the SMTP relay at your service provider instead. For more information, review this article.
550, “5.7.1”, The user or domain that you are sending to (or from) has a policy that prohibited the mail that you sent. Please contact your domain administrator for further details. For more information, review this article.
550, “5.7.1”, Unauthenticated email is not accepted from this domain.
550, “5.7.1”, Daily SMTP relay limit exceeded for customer. For more information on SMTP relay sending limits please contact your administrator or review this article.
552, “5.2.2”, The email account that you tried to reach is over quota.
552, “5.2.3”, Your message exceeded Google’s message size limits. Please review our size guidelines.
553, “5.1.2”, We weren’t able to find the recipient domain. Please check for any spelling errors, and make sure you didn’t enter any spaces, periods, or other punctuation after the recipient’s email address.
554, “5.6.0”, Mail message is malformed. Not accepted.
554, “5.6.0”, Message exceeded 50 hops, this may indicate a mail loop.
554, “5.7.0”, Too Many Unauthenticated commands.
555, “5.5.2”, Syntax error.

 

AOL

 

554 RTR:BB

  • AOL works with many ISPs to maintain lists of dynamic and residential IP addresses. Per our Email Guidelines, we do not accept mail from these addresses. If you are blocked by a RTR:BB error and have a fully qualified domain name (FQDN), please open a support request to lift the RTR:BB block. If you do not have a FQDN, please have your ISP create one for you and then open a support request.

554 RTR:CH

  • A computer, or computers, on your network may be compromised and sending mail that matches the signature of known spam. Before opening a support request, ensure you have a fully qualified domain name, get approved for a complaint Feedback Loop, scan your system for compromises and secure any issues.

554 RTR:RD

  • The reverse DNS of your IP Address is typical of a dynamic IP Address and/or has generated AOL member complaints. Ensure you have a fully qualified domain name and get approved for a Feedback Loop before opening a support request.
  • rDNS must be in the form of a fully qualified domain name. rDNS containing in-addr.arpa are not acceptable, as these are merely placeholders for a valid PTR record. rDNS consisting of IP addresses are also not acceptable, as they do not correctly establish the relationship between domain and IP address.
  • rDNS that may be similar to dynamic IP space (containing pool, dhcp, dyn, etc.) may be treated as suspect, and should therefore be changed to reflect a fully qualified domain name with a standard reverse DNS.

554 RTR:SC

  • This error message is indicative of a block due to successive dynamic blocks issued against your IP address. Before opening a support request, ensure you have a fully qualified domain name as Reverse DNS, scan your system for compromises and secure any issues.

554 RTR:DU

  • AOL uses the Spamhaus PBL to block mail from dynamic and residential IP addresses. Per our Email Guidelines, we do not accept mail from such addresses. If you believe your IP is listed in error, please contact your ISP directly and have them update their listing with the PBL. If:
    • your ISP reports that the IP is correctly listed in the PBL, and that you should be able to send mail from it, or
    • you were recently assigned IPs, have changed the rDNS on them, and allowed 48-72 hours for propagation time…and you are still getting the error, please open a support request.

554 RTR:GE

  • This is a transient error indicating a technical issue on AOL’s side. Please wait 24 hours and then try to resend your mail. . This error would be auto resolved and does not require a support request.

554 RTR:BL

  • This error message indicates that a permanent block has been placed against your IP due to poor reputation. If you were blocked recently, clean up your mailing list and apply for a complaint feedback loop before opening a support request.

 

554 HVU:B1

  • There is at least one URL or domain in your mail headers/hostname that is generating substantial complaints from AOL members and is blocked on our end. To fix the problem, please open a support request.

554 HVU:B2

  • There is at least one URL or domain in your email that is generating substantial complaints from AOL members and is blocked on our end. To fix the problem, please open a support request.

 

421 DNS:NR

  • The Reverse DNS lookup for your IP address is failing. This could be a transient issue. Confirm the IP that sends your mail, and then check the rDNS of that IP using our troubleshooting tools. If it passes, please wait 24 hours and then try resending your mail before opening a support request.
    • rDNS must be in the form of a fully qualified domain name. rDNS containing in-addr.arpa are not acceptable, as these are merely placeholders for a valid PTR record. rDNS consisting of IP addresses are also not acceptable, as they do not correctly establish the relationship between domain and IP address.
    • rDNS that may be similar to dynamic IP space (containing pool, dhcp, dyn, etc.) may be treated as suspect, and should therefore be changed to reflect a fully qualified domain name with standard reverse DNS.

 

554 RLY:B1

  • This error message is created by a dynamic block placed on an IP address by our system. Dynamic blocks are placed when the IP’s statistics break our threshold. These are automated blocks that are removed by the system within 24 hours once the complaints are again below the threshold.

554 RLY:B2

  • This error message indicates that a hard block has been placed against your IP address due to poor IP reputation. Resolution will require opening a support request once the IP reputation can be improved.

421 RLY:B3

  • The IP address you are sending from has been temporarily rate limited due to poor reputation.

554 RLY:BL

  • This error message indicates that a hard block has been placed against your IP address due to poor IP reputation. Resolution will require opening a support request once the IP reputation can be improved.

554 RLY:BD

  • This error message indicates that a hard block has been placed against your email because it has triggered too many anti-spam flags. This block is not against the IP. It targets specific types of email.

421 RLY:CH

  • A computer, or computers, on your network may be compromised and sending mail that matches the signature of known spam. Before opening a support request, ensure you have a fully qualified domain name, get approved for a complaint Feedback Loop, scan your system for compromises and secure any issues.

554 RLY:CH

  • A computer, or computers, on your network may be compromised and sending mail that matches the signature of known spam. Before opening a support request, ensure you have a fully qualified domain name, get approved for a complaint Feedback Loop, scan your system for compromises and secure any issues.

554 RLY:IR

  • The reverse DNS of your IP Address is typical of a dynamic/residential IP Address and has a high percentage of invalid recipient attempts. Before opening a support request, ensure you have a fully qualified domain name, get approved for a complaint Feedback Loop, scan your system for compromises and secure any issues.

554 RLY:SN

  • This error indicates you are sending email using a disallowed AOL.com Username as your FROM or REPLY-TO address, or as one of AOL’s affiliates from an unauthorized IP address. Example: Billing@aol.com

 

421 DYN:T1

  • The IP address you are sending from has been temporarily rate limited because it is not Whitelisted, unexpected increase in volume, or poor IP reputation.

421 DYN:T2

  • The IP address you are sending from has been asked to delay email delivery to AOL members due to a temporary issue with our mail system. This will be corrected by AOL and no changes should be necessary on your part. If the issue persists, feel free to open a support request with our postmasters.

 

554 CON:B1

  • The IP address has been blocked due to a spike in recent complaints, poor reputation or policy reasons. Please visit our Guidelines and best practices sections for more information on our Technical and policy requirements.

421 CON:B1

  • The IP address has been tempfailed due to a spike in recent complaints, poor reputation or policy reasons. Please visit our Guidelines and best practices sections for more information on our Technical and policy requirements.

 

554 DMARC:AOL

554 DMARC:F1

  • This message failed DMARC Evaluation and is being refused due to the policy provided by the From domain.

554 DMARC:F2

  • This message failed DMARC Evaluation because neither DKIM or SPF aligned with the policy provided by the From domain.

554 DMARC:SD

  • This message failed DMARC Evaluation because SPF was unaligned and DKIM passed in relaxed mode, however the policy provided by the From domain required strict alignment.

554 DMARC:SP

  • This message failed DMARC Evaluation because DKIM and SPF passed in relaxed mode, however the policy provided by the From domain required strict alignment.

554 DMARC:SS

  • This message failed DMARC Evaluation because DKIM was unaligned and SPF passed in relaxed mode, however the policy provided by the From domain required strict alignment.

554 DMARC:TE

  • This message failed DMARC Evaluation due to an error validating your SPF record, please retry the message.

 

421 MFF:DT

  • This mail appears to be from the future. Check the clocks on your DKIM signing host(s) and try again later.

421 MFF:MT

  • This mail appears to be from the future. Check the clocks on your MTA(s) and try again later.

521 Recipient address rejected

This error indicates that the AOL member email address no longer exists or the address is misspelled.

AOL will not accept delivery of this message

This is a permanent bounce due to:

  • RFC2822 From domain does not match the rDNS of sending server.
  • RFC 2822 FROM address does not have an A record and is not a valid domain.
  • IP has a poor reputation and mail is sent to multiple recipients.
  • There are multiple From address in the mail headers and the IP reputation is poor.

ESMTP Not accepting connections/Service unavailable:

This is a permanent bounce due to but not limited to below reasons:

  • IP reputation is poor and recent spike in mail volume
  • IP is not part of AOL Whitelist

550 “Username” Is Not Accepting Mail From This Sender

This error indicates that the AOL member has configured their account, possibly inadvertently, to only accept mail from certain addresses and/or domains. The member will have to change their mail settings in order to receive mail from you. AOL Postmasters cannot override these settings. We respect our member’s privacy and their ability to control their own inbox. AOL Postmasters cannot forward the mail for you. AOL members that have set this rule accidentally can view instructions on how to change the setting, or contact AOL Member Services.

 

 

 

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