Why do some recipients see placeholder text (e.g., "Header 01", "Button Text") in their emails while others see the correct content?

This issue typically occurs due to incomplete Localization settings in the email configuration.

The Cause

This happens when the Default content is fully configured with the correct text, but a specific Language variant (e.g. Spanish, French) has been added to the configuration and left with default placeholder elements.

• Users falling under the Default locale receive the correct content.
• Users matching the specific Language profile receive the incomplete version containing placeholders like "Header 01" or non-functional buttons.

How to Fix

Open the email in the editor and use the Language selector in the top bar. Content you have not translated yet for the selected language is shown dimmed, so you can see exactly what is missing. Then choose one of the following:

1. Auto-translate: click Auto-translate in the language bar to fill the missing texts — body text, buttons, lists, menu items, image alt text, subject line, preheader and footer links. Translations you already wrote are kept.
2. Complete the localization manually: switch to the language and copy the content over from the Default variant.
3. Remove the extra language: if your Default content is already written in the desired language, unselect that language in the Language selector. Its translations are dropped and every user receives the Default content.

How to Fix for Affected Users (Resend)

Emails that have already been delivered cannot be updated remotely. To fix the issue for users who received the placeholders, you must resend the campaign. To avoid resending to the entire audience, follow these steps:

1. Create a new Segment.
2. Use the exact criteria from your original audience.
3. Add an additional condition (AND): Language equals the language code that was incomplete — the tag stores codes such as es or fr, not language names.
4. Send the corrected email to this new segment. This targets only the users who originally received the broken version.