There are a number of different date formats used around the world, and the approach for changing to any of them is broadly the same. In this tutorial we'll show how to change from the default US format to the dd/mm/yyyy format used in most other English-speaking countries and those speaking many other languages. As date formats are generally language-specific (or in the case of English, dialect-specific) we'll be editing two Zen Cart language files to make this change.
1. open file includes/languages/<YOUR_TEMPLATE>/<YOUR_LANGUAGE>.php
(if this file doesn't exist, create it by copying the file includes/languages/<YOUR_LANGUAGE>.php to this location).
2. find this section:
@setlocale(LC_TIME, 'en_US.ISO_8859-1');
define('DATE_FORMAT_SHORT', '%m/%d/%Y'); // this is used for strftime()
define('DATE_FORMAT_LONG', '%A %d %B, %Y'); // this is used for strftime()
define('DATE_FORMAT', 'm/d/Y'); // this is used for date()
define('DATE_TIME_FORMAT', DATE_FORMAT_SHORT . ' %H:%M:%S');
and replace with:
@setlocale(LC_TIME, 'en_GB.ISO_8859-1');
define('DATE_FORMAT_SHORT',
...