Adding a message to the admin order update email
Since Zen Cart 1.5.7, the capability to add a static message to the admin order update email has been built in.
In Zen Cart 1.5.8 and higher, the file containing the message is located at admin/includes/languages/english/lang.email_extras.php
.
In Zen Cart 1.5.7, the file containing the message is located at admin/includes/languages/english/email_extras.php
.
Edit this file, and set the defined constant EMAIL_ORDER_UPDATE_MESSAGE
with your additional message and save the file.
There is also a notifier called ZEN_UPDATE_ORDERS_HISTORY_SET_ORDER_UPDATE_MESSAGE
which fires when the message is being added, providing the opportunity for customization.
You can test your changes to the order update email simply by updating an order on the order details page.