In the configure.php files there's a section:
PHP Code:
// * DIR_WS_* = Webserver directories (virtual/URL)
// these paths are relative to top of your webspace ... (ie: under the public_html or httpdocs folder)
define('DIR_WS_CATALOG', '/');
define('DIR_WS_HTTPS_CATALOG', '/');
define('DIR_WS_IMAGES', 'images/');
define('DIR_WS_INCLUDES', 'includes/');
define('DIR_WS_FUNCTIONS', DIR_WS_INCLUDES . 'functions/');
define('DIR_WS_CLASSES', DIR_WS_INCLUDES . 'classes/');
define('DIR_WS_MODULES', DIR_WS_INCLUDES . 'modules/');
define('DIR_WS_LANGUAGES', DIR_WS_INCLUDES . 'languages/');
define('DIR_WS_DOWNLOAD_PUBLIC', DIR_WS_CATALOG . 'pub/');
define('DIR_WS_TEMPLATES', DIR_WS_INCLUDES . 'templates/');
Have you got this section intact? - particularly the last line:
PHP Code:
define('DIR_WS_TEMPLATES', DIR_WS_INCLUDES . 'templates/');
(NB: Yours will probably (ought to) show /shop/ in the top bits.)