| Error code | Explanation |
|---|---|
| JFE040000 | Rejected due to high probability of spam. Please reach out to us if you need to get more details: - For Private Email and Shared Hosting users: please contact us via Live Chat at https://www.namecheap.com/help-center/live-chat/ - For Spacemail users: please reach us out via Live Chat at https://www.spaceship.com/about/contact-us/ |
| JFE040001 | Our system classified the content of your email as being similar to known spam patterns. Please consider changing the wording of your message to avoid phrases and sentences common for unsolicited emails. You may find suggestions on improving your content in our guide: Why emails go to spam and what to do |
| JFE040002 | The message contains a file with an untrustworthy extension. Please refrain from adding attachments with this extension, or use an alternative method to share the file. |
| JFE040003 | The domain in your message has a poor reputation and is on a blocklist. Please contact the relevant blocklist provider to request delisting. |
| JFE040004 | Your email content corresponds with (or is similar to) a known spam pattern that is filtered by our system. You may find suggestions on improving your content in our guide: Why emails go to spam and what to do |
| JFE040005 | The domain in your message has a poor reputation and is on a blocklist. Please contact the relevant blocklist provider to request delisting. |
| JFE040006 | The URI in your message has a poor reputation. Please remove it and try again. |
| JFE040007 | Your message contains a URL with phishing-related content. To resolve this, remove or replace the URL in question. If the domain in the URL is in your administration, we recommend removing it from blocklists first. |
| JFE040008 | The subject line in your email contains only uppercase letters. Consider removing excessive capital letters from the subject line as it can be considered as spam-like behavior. |
| JFE040009 | Your "multipart/alternative" message contains an odd number of URIs. Check that both the plain text and HTML versions of your message have the same number of URIs. |
| JFE040010 | The "Message-ID" header is incorrectly formatted or missing. To resolve this, ensure that the email server generates unique and properly formatted "Message-ID" headers for each email, following the RFC 5322 guidelines. |
| JFE040011 | The sender seems to be forged, as the email address in the "From" field does not correspond to the mailbox from which the email is sent ("envelope-from" field). Please make sure that the sender is the same in both the "From" and "envelope-from" fields. |
| JFE040012 | The message body contains a text part encoded in Base64 format that does not contain any 8-bit characters (which means it might contain binary data or a malicious script). Remove Base64 encoding to allow your message to be sent. |
| JFE040013 | The message’s "MIME-Version" header is incorrectly formatted. MIME headers are case-sensitive. You used "Mime-Version", but the correct version according to RFC 822 is "MIME-Version". Please correct the header formatting before resending the email. This can be adjusted in your script, mail client software, or mailing application settings. |
| JFE040014 | The HTML and text parts of your message do not match. Please ensure the content is the same in both, then try sending the message again. |
| JFE040015 | The subject of the message contains a "Re:" prefix, but it does not appear to be a reply. Please avoid using the "Re:" prefix unless you are responding to a message. To reply properly, use the Reply button in your Webmail or email client. |
| JFE040016 | The subject line in your message contains non-7-bit characters and must be encoded according to RFC rules (RFC 2047 and RFC 6532) to ensure correct rendering across email platforms. To fix this, ensure the special characters in the subject line are encoded. If you’re using any mailing software, check it for misconfigurations. |
| JFE040017 | The message is missing its "Message-ID" header. To resolve this, make sure your email server or client generates and includes a unique "Message-ID" for each outgoing message. |
| JFE040018 | Subject line contains currency symbols which may be indicative of spam or phishing. Please remove the currency signs or terms commonly associated with financial solicitations from the subject line. |
| JFE040019 | The message has a date header specifying a timestamp in the past. To fix this, ensure that the system time on your email server is correctly configured and synchronized with a reliable time source before resending the email. |
| JFE040020 | The message has a date header specifying a timestamp in the future. To fix this, ensure that the system time on your email server is correctly configured and synchronized with a reliable time source before resending the email. |
| JFE040021 | The message contains an IPFS (Interplanetary File System) gateway URL, which is often associated with malicious emails. Please refrain from using IPFS URLs in messages, and consider using alternative non-IPFS links. |
| JFE040022 | The subject line in the message is heavily encoded in Base64 format, even though it lacks non-Unicode characters. This may result in the recipient's mail client decoding the subject incorrectly. To fix the issue, avoid encoding subjects, specifically as mail clients should do it for you where needed. |
| JFE040023 | The subject line ends with a question mark which can be a characteristic of spam or phishing attempts. Please remove the question mark in the subject line. |
| JFE040024 | The message is missing the "MIME-Version" header. To fix this, ensure your email includes a "MIME-Version" header with the appropriate version number. This can usually be set in your mailing script or email application. |
| JFE040025 | The introduction at the beginning of the email has triggered our anti-spam filter. Please reformat the introduction part in the beginning of the email. |
| JFE040026 | The recipients in the message’s "envelope-to" and "To" headers do not match, which could indicate a possible spoofing attempt. Please make sure you provide the same recipients in both the "envelope-to" and "To" fields. |
| JFE040027 | The "From" header in your message contains encoded characters, but all symbols are 7-bit, so Base64 encoding is unnecessary. Please check your scripts or mailing applications — there may be a non-printable or malicious character that needs to be removed. |
| JFE040028 | The message content primarily consists of URLs, which can be a characteristic of spam or phishing emails. To address this, consider adding more meaningful content to your email, and avoid messages that only contain links. |
| JFE040029 | The message contains the email address that has a poor reputation. Please contact the relevant blocklist provider to request delisting. |
| JFE040030 | Content-Transfer-Encoding (CTE) for some parts of the email is set to 7-bit, which may not be appropriate for certain content types. To fix this, ensure that the CTE is correctly configured based on the content, using alternatives like quoted-printable or Base64 for non-ASCII characters. Also, you can check the mailing script or the mailing software you are using to adjust the Content-Transfer-Encoding appropriately. |
| JFE040031 | The message is missing a plain text part, which is considered untrustworthy and can also affect accessibility. Please either add a plain text version of the email or check that your email client is configured properly to generate this when a message is created. |
| JFE040032 | The "Reply-To" header in the message contains a domain that differs from the one used in the "From" header. This can be seen as untrustworthy, since spammers often use this technique to spoof replies. Please correct this and resend your message. |
| JFE040033 | The recipients in the message seem to be auto-generated. Please avoid sending emails to more than 5 recipients at once if the addresses are similar or seem like automatically generated addresses. |
| JFE040034 | X-Mailer header indicates a very old Mail User Agent version. Update your mailing software to the latest version to resolve this issue. |
| JFE040035 | Your message contains a suspicious URL. To resolve this, remove or replace the URL in question. |
| JFE040036 | The display name in the "From" header is the same as the sending email address. Please avoid using email addresses as display names, as this is often associated with spam-like behavior. |
| JFE040037 | The message is missing the "Date" header, which is essential in indicating when the message was sent. Without it, the message is not compliant with RFC 5322 formatting standards. Please add a "Date" header in the correct format (e.g., Date: Wed, 20 Mar 2025 12:34:56 +0000) and try sending your email again. |
| JFE040038 | The "Reply-To" header in the message is the same as the "To" address, but it should lead to the same domain as the "From" address. Please adjust the "Reply-To" address and resend your message. |
| JFE040039 | The message is missing the "To" header. This can occur if the mailing script or agent is misconfigured, or due to a mail server issue. Please ensure the "To" header is present and try resending the email. |
| JFE040040 | Rejected due to high probability of spam. Please reach out to us if you need to get more details: - For Private Email and Shared Hosting users: please contact us via Live Chat at https://www.namecheap.com/help-center/live-chat/ - For Spacemail users: please reach us out via Live Chat at https://www.spaceship.com/about/contact-us/ |
| JFE040041 | The local-part (the portion before the "@" symbol) of the recipient's email address — including those in the "To", "CC", or "BCC" fields — must follow the formatting rules defined in RFC 5321. This includes restrictions on characters, length, and placement of special symbols. For example, user name@example.com are invalid, while username@example.com is valid. Please correct the local-part format according to RFC 5321 before resending your message. |
| JFE040042 | According to RFC 5322, a space must separate the header name from its value. If it’s missing, the message will be rejected. For example, Subject:Hello is incorrect, while Subject: Hello is correct. Please review your headers and ensure there is a space after the colon before resending the message. |
| JFE040043 | The "From" header specifies the sender and is required by RFC 5322. If it's missing, the email is considered incomplete and will be rejected. Make sure your email-sending application or script includes the "From" header (e.g.,From: sender@example.com), then resend your message. |
| JFE040044 | Only one "From" header is allowed in an email, according to RFC 5322. Multiple "From" headers are invalid and will be rejected. Please review the headers, keep only one "From" header, and resend the message. |
| JFE040045 | The "From" header contains an incorrectly formatted or invalid email address. According to RFC 5322, the format should be Sender, where “Sender” is the display name,user is the local-part, and example.com is the domain. Please correct this and try resending the message. |
| JFE040046 | The domain used in the "From" header must be a fully qualified domain name (FQDN) according to RFC 5321. This means it should include both the domain name and the top-level domain (e.g., example.com). Please correct this and resend your message. |
| JFE040047 | The domain used in MAIL FROM in an email's envelope needs to be a fully qualified domain name (FQDN) according to RFC 5321. This means it should include both the domain name and the top-level domain (e.g., example.com). Please correct this and try resending the email. |
| JFE040048 | The "MAIL FROM" address in the email envelope is incorrectly formatted or invalid. According to RFC 5321 specifications, the "MAIL FROM" address must be a properly formatted address like |
If the problem continues with any of these errors, please contact our Support Team via Live Chat:
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