S.C. Code Ann. § 15-9-280
(c) The Secretary of State shall immediately forward by certified mail one of the copies of the process or the notice, order, pleading, or process in proceedings before the Department of Insurance to the defendant in the court proceeding or to whom the notice, order, pleading, or process in the administrative proceeding is addressed or directed at its last known principal place of business and shall keep a record of all process so served on him which shall show the day and hour of service. The service is sufficient if: