3 ms·Small nit: S-1-5-18 is the SID+RID for "NT AUTHORITY\SYSTEM". S-1-5 is just the "NT AUTHORITY" prefix.by akira2501 12y agoSmall nit: S-1-5-18 is the SID+RID for "NT AUTHORITY\SYSTEM". S-1-5 is just the "NT AUTHORITY" prefix.