Why would a customer receive an email intended for another customer with the wrong email in the TO field?

Email marketer from Mailjet shares that issues with variable data insertion (mail merge) can cause the wrong data to be inserted into the 'To:' field. This is often due to errors in the CSV file or incorrect variable tagging in the email template.

Email marketer from Neil Patel's Blog explains that errors in email list segmentation can cause emails to be sent to the wrong recipients. Incorrectly applied filters or tags can lead to misidentification of audience segments.

Email marketer from Reddit suggests that if account compromise has occurred, a malicious actor may alter recipient information or email content to redirect emails, leading to incorrect 'To:' fields. Always check security measures.

Email marketer from Email Geeks advises to make sure the mixup actually happened on a technical level and not a human one, suggesting to check if the CRM or database has the correct data input into the fields for the recipient.

Email marketer from Quora answers that if the CRM integration is faulty, emails could be triggered incorrectly, causing email intended for customer B to be sent to customer A with the wrong “To” field.

Email marketer from Litmus explains that errors in dynamic content implementation can result in the wrong 'To:' field being displayed. This is common when using complex conditional logic or personalization rules within the email template.

Email marketer from Email on Acid shares that insufficient testing and quality assurance (QA) can lead to errors like incorrect recipient data in the 'To:' field. Thorough testing with seed lists and different email clients is crucial.

Email marketer from StackOverflow shares that debugging mail merge scripts is essential because a common mistake is to unintentionally substitute one person's data for another's due to loop errors or wrong index referencing, leading to emails with incorrect 'To:' fields.

Email marketer from SuperOffice answers problems related to synchronizing databases. The wrong information in the “To” field may arise because customer databases are not correctly synchronized.

Email marketer from Email Geeks asks if the TO field is showing one email as the “display name”, but the actual email being the real recipient, which would cause customer A to “see” customer B’s email.

Email marketer from ActiveCampaign answers issues with automation is a major contributor. If automation rules are set up incorrectly, they could trigger the wrong emails or insert the incorrect recipient details.

Expert from Spam Resource explains that faulty list management practices often lead to sending emails to the wrong recipients. This involves mishandling opt-in processes, data entry errors, or simply using outdated lists.

Expert from Word to the Wise responds that human error in email marketing can result in sending emails with incorrect 'To:' fields. Factors that contribute to this are lack of training, fatigue, or inadequate processes.

Expert from Email Geeks shares that he agrees with Tom's TO field theory based on previous experience.

Expert from Email Geeks explains that the recipient an email is delivered to is unrelated to the address in the To: field and suspects a mistake in the sending or message composition code.

Expert from Email Geeks suggests the full email header might confirm the TO field theory, but recommends asking the smartest developer about how this could happen.

Documentation from SendGrid explains the difference between the SMTP envelope and the email header. The SMTP envelope (specified during the SMTP transaction) dictates where the email is delivered, whereas the header 'To:' field is just part of the email body and is not used for routing.

Documentation from Microsoft explains that in Exchange Server environments, address rewriting rules, if misconfigured, can inadvertently alter the 'To:' field of outgoing messages. Incorrect regular expressions or logic errors can lead to unintended address substitutions.

Documentation from ietf.org explains that the 'To:' field in an email header is for informational purposes and does not dictate the actual delivery of the message. The mail transfer agent relies on the RCPT TO command during the SMTP transaction to determine the recipients.

Documentation from Oracle answers issues from the core email systems, like Oracle, may contain errors that lead to incorrect routing or the wrong information in the header, particularly when complex rules or setups are implemented.

Documentation from Postfix.org explains that misconfiguration of virtual aliases in the mail server can cause emails intended for one address to be routed to another. This is a server-side configuration issue.