http://forge.prestashop.com/browse/BOOM-3486
Error: When adding a new language in the backend (localization->languages), there is no option to enter the locale, resulting in an empty locale field in the table ps_lang.
This results in a smarty error on frontend when selecting the new language:
{code}
SmartyException in smarty_internal_templatebase.php line 129:
Unable to load template file ‘\index.tpl’ {code}
User’s suggested solution:
As soon as I manually add a locale in the database, the error goes away.
Table: ps_lang
Add the missing locale to the table
Normally adding/importing a new language should go to: Translation > Add/Update a new language (or through the localization page)
But there are times when languages may be required to be added manually and this causes the issue.