function OnSystemAccount(): Boolean;
const
 cnMaxNameLen = 254;
var
 sName: string;
 dwNameLen: DWORD;
begin
 dwNameLen := cnMaxNameLen - 1;
 SetLength(sName, cnMaxNameLen);
 GetUserName(PChar(sName), dwNameLen);
 SetLength(sName, dwNameLen);
 if UpperCase(Trim(sName)) = 'SYSTEM' then Result := True
 else
  Result := False;
end;