Title 14, Chapter 2, Section 504
(a) A corporation's registered agent is the corporation's agent for
service of process, notice, or demand required or permitted by law
to be served on the corporation.
(b) If a corporation has no registered agent or the agent cannot
with reasonable diligence be served, the corporation may be served
by registered or certified mail or statutory overnight delivery,
return receipt requested, addressed to the secretary of the
corporation at its principal office. Service is perfected under
this subsection at the earliest of:
(1) The date the corporation receives the mail;
(2) The date shown on the return receipt, if signed on behalf of
the corporation; or
(3) Five days after its deposit in the mail, as evidenced by the
postmark, if mailed postage prepaid and correctly addressed.
(c) This Code section does not prescribe the only means, or
necessarily the required means, of serving a corporation.