LogFilter is an ISAPI log filter for the Microsoft IIS 3 websever that will add the USER_AGENT and URL_REFERER fields to your Microsoft IIS log files.

The User_Agent field indicates the Web Browser and Operating System being used by the visitor. This information can be used to determine the browser capabilities (Java, JavaScript, ActiveX, etc) of your visitors. The Url_Referer field indicates the page visitors followed to reach your site. This information can be used to determine how people are finding your site.

The ISAPI filter works by appending the User_Agent and Url_Referer data to the IIS TargetURL field. The IIS LogFilter enhanced log file will appear as follows:

IIS Standard log Format:

ClientIP, UserName, RequestDate, RequestTime, Service, ServerName, ServerIP, ProcessingTime, BytesReceived, BytesSent, Status, Win32Status, Operation, TargetURL, Parameters

LogFilter log Format:

ClientIP, UserName, RequestDate, RequestTime, Service, ServerName, ServerIP, ProcessingTime, BytesReceived, BytesSent, Status, Win32Status, Operation, TargetURL, UserAgent, UrlReferer, Parameters

Installation Instructions:

1. Unzip archive LogFilter.zip (contains LogFilter.dll) into a temporary directory
2. Move the LogFilter.dll into your IIS install directory on your server (usually c:\winnt\system32\inetsrv\).
3. Run the registry editor REGEDT32.EXE
4. Go to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\W3SCVC\Parameters key
5. Edit the "Filter Dlls" value by double clicking on it.
6. Append the path of the filter ,c:\winnt\system32\inetsrv\LogFilter.dll to the value (include the leading comma).
7. Save the value by clicking 'OK'
8. Exit REGEDT32.EXE
9. Stop and restart the "World Wide Web Publishing Service".