We've received inquiries regarding the user-agent string that the Windows RSS Platform uses when making HTTP requests to servers. This is particularly interesting to services that provide statistics to their users indicating how many users are reading content via web browsers vs. aggregators.

There are two distinct instances where a user-agent string is used:

  1. The user is not subscribed to the feed. The user navigates to a feed and IE7 presents a preview of the content.
  2. The user is subscribed to the feed. The RSS Platform retrieves the feed content on a schedule (or on demand).

In the first case it's the web browser that is making the HTTP request and hence the IE7 user-agent string is used. For example, on Windows XP, this string looks like this: 

Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)

In the second case it is the RSS Platform that makes the HTTP request and hence the following string is used on Windows XP:

Windows-RSS-Platform/1.0 (MSIE 7.0; Windows NT 5.1)
and on Windows Vista:
Windows-RSS-Platform/1.0 (MSIE 7.0; Windows NT 6.0)

The RSS Platform user-agent string reflects on the version of Windows on which it is running, and the version of IE that is present on the system.

Note 1: The current beta 2 build of the RSS Platform uses a slightly different string, that is not compliant with the HTTP spec. The difference is that spaces are used in the token instead of dashes. Future builds will use exactly the string shown above.

-Walter vonKoch