N.C. Gen. Stat. § 90-14.3
Any notice required by this Chapter may be served either personally by an employee of the Board or by an officer authorized by law to serve process, or by registered or certified mail, return receipt requested, directed to the licensee or applicant at his last known address as shown by the records of the Board. If notice is served personally, it shall be deemed to have been served at the time when the officer or employee of the Board delivers the notice to the person addressed or delivers the notice at the licensee's or applicant's last known address as shown by records of the Board with a person of suitable age and discretion then residing therein. Where notice is served by registered or certified mail, it shall be deemed to have been served on the date borne by the return receipt showing delivery of the notice to the licensee's or applicant's last known address as shown by the records of the Board, regardless of whether the notice was actually received or whether the notice was unclaimed or undeliverable for any reason.
N.C. Gen. Stat. § 90-14.3