Hi Paul, one way this can happen if the production version of your protocol has changed, and this new version contains an additional port for communication, compared with the older version. This will result in the element.xml missing information to start your element.

Best thing to do is to edit your element and see if there are any red fields there to fill in info. If not still save the config and restart the element, as this will still add proforma fields in the element.xml requiring the element to start, if the port requires no manual config.