Bounces occurring despite using UTF-8 HTML with copyright characters are typically caused by a combination of factors. Email's default 7-bit US-ASCII encoding necessitates MIME for extended characters. Sending high-ASCII/Unicode as 7-bit Content-Transfer-Encoding, rather than CTE binary or quoted-printable, results in issues. Encoding discrepancies between the HTML editor, ESP, email headers, and client-side support contribute to the problem. Older servers may lack full UTF-8 support. Solutions include ensuring the 'Content-Type' header specifies 'charset=UTF-8', using HTML entities as a workaround, and thorough testing across various email clients. Proper configuration of the ESP to send as UTF-8 or quoted-printable is also crucial. Validating the full message helps ensure correct handling of special characters.
9 marketer opinions
Bounces related to UTF-8 encoding and special characters often arise from several issues. Even if your HTML is UTF-8 encoded, the email server or ESP might be sending emails as 7-bit ASCII, which doesn't support special characters. Inconsistencies in character encoding settings between your email editor, ESP, and the email client can also cause problems. Older email servers might not fully support UTF-8, and testing across different email clients is crucial to ensure proper rendering. Other solutions include using HTML entities for special characters and ensuring your sending platform is configured to use UTF-8 or quoted-printable encoding.
Marketer view
Email marketer from Stack Overflow shares that even if your HTML is UTF-8, the email server might be sending the email as 7-bit ASCII. You need to ensure your email sending software (or ESP) is configured to send emails as UTF-8 or quoted-printable to handle non-ASCII characters correctly.
16 Apr 2023 - Stack Overflow
Marketer view
Email marketer from Mailjet explains that incorrect character encoding, especially when using special characters like copyright symbols or accented letters, can lead to bounces if the email client or server doesn't support the encoding. UTF-8 is recommended, but the email headers must also declare the correct encoding.
14 Jan 2022 - Mailjet
3 expert opinions
Bounce issues with UTF-8 and copyright characters often stem from sending high-ASCII/Unicode characters as Content-Transfer-Encoding: 7bit instead of CTE binary or quoted-printable. Discrepancies between declared and actual encoding, and sending systems mishandling non-ASCII characters are also causes. A short-term workaround is using HTML entities, though not ideal. Validating the full message is crucial.
Expert view
Expert from Email Geeks explains the bounce issue is likely due to sending high-ascii/Unicode characters as Content-Transfer-Encoding: 7bit. They suggest sending as CTE binary or quoted-printable. Also if your ESP tells you to not use said characters in your email content get a better ESP.
21 Mar 2024 - Email Geeks
Expert view
Expert from Email Geeks suggests a short-term workaround to use HTML entities for everything, but acknowledges it's not ideal.
11 Jul 2024 - Email Geeks
5 technical articles
Email bounce issues with UTF-8 HTML containing copyright characters often result from the default 7-bit US-ASCII encoding limitation of email messages, necessitating MIME for handling extended character sets like UTF-8. Incorrectly declared character sets in the email header can lead to misinterpretation by receiving servers, causing bounces or display problems. While UTF-8 is recommended, compatibility varies among email clients, making testing crucial. Proper declaration in the 'Content-Type' header with 'charset=UTF-8' is essential to avoid these issues.
Technical article
Documentation from W3.org explains that HTML emails must have the encoding set to UTF-8 to avoid cross email client compatibility issues.
21 Nov 2024 - W3.org
Technical article
Documentation from Oracle explains that if the character set is not correctly declared in the email header, the receiving mail server might misinterpret the characters, leading to display issues or bounces. Ensure the 'Content-Type' header specifies 'charset=UTF-8'.
13 Jul 2021 - Oracle
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