Service by Commission. The Commission shall serve all notices, orders, and decisions, by: Electronic means: To each party’s attorney of record who has registered with CompHub and consents; and To each unrepresented party who has registered with CompHub and consents; or First-class mail. Commission notices, awards, orders, and decisions are sent by electronic means or mailed by first-class mail on the date of issue shown on the notice, award, order, or decision. Service by Parties. Except as otherwise provided in these regulations, a copy of every paper, form, or document filed with the Commission by a party shall be served promptly on all other parties. If a party is represented by an attorney, service shall be made upon the attorney unless service on the party is directed by the Commission. Service may be made by: Handing the papers to the party or attorney; Leaving the papers at that person's office with an individual in charge, or, if there is no one in charge, leaving the papers in a conspicuous place in the office, or, if the office is closed or the person has no office, leaving the papers at the person's usual place of residence with an individual of suitable age and discretion residing there; Mailing the papers to the address most recently stated in a paper filed by the party or attorney, or if not stated, to the last known address; or Electronic means. Service by mail is complete upon mailing. Service by electronic means is complete upon sending the electronic filing or service, but service is not effective if the person who filed with the Commission or the person who sent by electronic means learns that the paper did not reach the person to be served. This regulation does not make the Commission responsible for notifying a person who filed the paper with CompHub that an attempted transmission by CompHub failed. But a filer who learns that the transmission failed is responsible for making effective service. Each paper filed that is required to be served shall be accompanied by a certificate of service, signed by the party or the party's attorney, showing the date and manner of making service on each of the other parties.