Figure 7-9 is an example of a portion of security iog from a computer running the Windows operating system. It shows that a user named "rjones" unsuccessfully tried to log onto computer named "payroll server." The person analyzing the log must seek to determine the reason for this failed log-on attempt. It may be that rjones is a legitimate user who forgot the password. Another possibility is that rjones is a legitimate user but is not authorized to access the payroll server. Yet another possibility is that the user ID is itself invalid, in which case this may represent an attempted attack by an external intruder.