What are common reasons for the "syntax error: unrecognized tag 'config_load'" error in Smarty when using PHP?

The "syntax error: unrecognized tag 'config_load'" error in Smarty occurs when the config_load tag is not recognized by the Smarty template engine. This error can be solved by making sure that the necessary Smarty configuration settings are properly set up to allow the use of the config_load tag. Additionally, ensure that the Smarty version being used supports the config_load tag.

// Set up Smarty configuration settings to allow the use of config_load tag
$smarty = new Smarty();
$smarty->configLoad('config_file.conf');