S.C. Code § 31-15-360
Complaints or orders issued by a public officer pursuant to an ordinance adopted under this article shall be served upon persons either personally or by registered mail, but if the whereabouts of such persons is unknown and cannot be ascertained by the public officer in the exercise of reasonable diligence and the public officer shall make an affidavit to that effect, then the serving of such complaint or order upon such persons may be made by publishing it once each week for two consecutive weeks in a newspaper printed and published in the county or, in the absence of such newspaper, in one printed and published in the municipality and circulating in the county. A copy of such complaint or order shall be posted in a conspicuous place on the premises affected by the complaint or order. A copy of such complaint or order shall also be filed with the clerk of court of the county in which the dwelling is located and such filing of the complaint or order shall have the same force and effect as other lis pendens notices provided by law.
S.C. Code § 31-15-360