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After updating the configuration file(s), you need to run the "ezpgenerateautoloads.php" script, in order to add the information about all PHP class definitions of this extension to the "<eZ_Publish_root_folder>/exponential_legacy/var/autoload/ezp_extension.php" file, otherwise Exponential might not be able to execute the PHP code of the newly added extension. The following example shows how to run the script.
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The script will look for class definitions in the "extensions" directory and update the "<eZ_Publish_root_folder>/exponential_legacy/var/autoload/ezp_extension.php