Service of process in any suit, action or proceeding or service of any notice or demand required or permitted by law to be served on a foreign corporation may be made on a foreign banking corporation holding a certificate of authority by service thereof on the registered agent of such foreign banking corporation. Whenever any foreign banking corporation holding a certificate of authority fails to appoint or maintain a registered agent upon whom service of legal process or service of any such notice or demand may be had, or whenever such registered agent cannot with reasonable diligence be found at the registered office of such foreign banking corporation, or whenever the certificate of authority of any such foreign banking corporation is revoked, then in every such case the Commissioner shall be irrevocably authorized as the agent and representative of such foreign banking corporation to accept service of any process or service of any notice or demand required or permitted by law to be served on such foreign banking corporation. Service on the Commissioner of any such process, notice or demand against any such foreign banking corporation shall be made by delivering to and leaving with him, or with any official having charge of the banking department of his office, duplicate copies of such process, notice or demand. If any process, notice or demand is served on the Commissioner, he shall immediately cause a copy thereof to be forwarded by registered mail addressed to such foreign banking corporation at its principal office as the same appears on his records. Any service so had on the Commissioner shall be returnable in not less than 30 days.
     Nothing in this Act limits or affects the right to serve any process, notice or demand required or permitted by law to be served upon a foreign corporation in any other manner now or hereafter permitted by law.
     The Commissioner shall keep a record of all processes, notices and demands served upon him by this Section and shall record therein the time of such service and his action with reference thereto.