@Mario Tigua The File Filter property in the listFile processor does not support NiFi Expression Language. If yo float your cursor of the question mark icon to the right of a property name it will display a pop-up window that will tell you if this property will support NiFi expression language. - This property expects a java regular expression instead. - Thank you, Matt - If you found this answer addressed your question, please take a moment to login in and click the "ACCEPT" link. ... View more