IIS4.0 May Log Incorrect Values for "Bytes Sent" Field in W3C Extended Log

ID: Q248819

The information in this article applies to:

Microsoft Internet Information Server version 4.0

SYMPTOMS

When using W3C Extended Log Format, Microsoft Internet Information Server (IIS) 4.0 should log the number of bytes sent by the server to the client in the sc-bytes field. However, if an HTTP request is cancelled when downloading a file, the log file reflects the size of the file being transferred and not the number of bytes really sent to the client.

RESOLUTION

A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next Windows NT service pack that contains this fix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

The English version of this fix should have the following file attributes or later:


   Date      Time    Version      Size    File name     Platform
   -------------------------------------------------------------
  12/16/99  22:40    4.2.0735    185.248 infocomm.dll   x86
  12/16/99  22:41    4.2.0735     38.256 ssinc.dll      x86
  12/16/99  22:41    4.2.0735     25.360 sspifilt.dll   x86
  12/16/99  22:41    4.2.0735    228.464 w3svc.dll      x86

STATUS

Microsoft has confirmed this to be a problem in Internet Information Server 4.0.

MORE INFORMATION

Using this fix, IIS will not log the total size of the file being transferred anymore. However, the logged value may be less than the number of bytes really sent to the client. The behavior is caused by the design of the network mechanisms (AFD driver and Transmit File Winsock API) used by IIS to transfer file data over a connected socket session.

Additional query words:

Keywords : kbiis400
Version : winnt:4.0
Platform : winnt
Issue type : kbbug