N.C. Gen. Stat. § 1-477

The defendant may, within three days after the service of a copy of the affidavit and undertaking, notify the sheriff personally, or by leaving a copy at his office in the county seat of the county, that he excepts to the sufficiency of the sureties. If he fails to do so, he is deemed to have waived all objection to them. When the defendant excepts, the sureties must justify on notice, in like manner as upon bail on arrest. The sheriff is responsible for the sufficiency of the sureties until the objection to them is either waived as above provided, or until they justify, or until new sureties are substituted and justify. If the defendant excepts to the sureties he cannot reclaim the property as provided in the succeeding section [G.S. 1-478].