Substatus Error Codes in Log Files
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1
When enabled, substatus error codes are written to IIS log files whenever a client request fails.
Important
You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /user:Administrative_AccountName "mmc %systemroot%\system32\inetsrv\iis.msc".
Procedures
To log substatus error codes
In IIS Manager, expand the local computer, expand the Web Sites folder, right-click the Web site, and click Properties.
On the Web Site tab, ensure that the Enable logging check box is selected.
In the Active log format list box, click W3C Extended Log File Format.
Click Properties.
Click the Advanced tab, and under Extended properties, select the Protocol Substatus check box.
Click OK twice.
Related Information
For an explanation of W3C Extended logging fields, including a detailed technical breakdown of the time-taken field, see W3C Extended Log File Format.
For more information about HTTP status codes (100 - 500) see HTTP Status Codes in IIS 6.0.
For information about client error codes (400 - 404) and how to troubleshoot common request problems, see HTTP 40x -- Client Error Codes.