Web Pages May Not Display Correctly When You Deny the Application/Octet-Stream Content Type

This article was previously published under Q319073
This article has been archived. It is offered "as is" and will no longer be updated.
Web servers use the application/octet-stream content type for any unknown content type. Because this can include any kind of document, when you (the administrator) allow this kind of content, this can provide an open door to the browser computer for all kinds of software anomalies.

Additionally, this content type is included in the Application content group that is preconfigured in Internet Security and Acceleration Server.

Therefore, you may decide that denying either this content type or the Application content group is a good method to protect your intranet against viruses or Trojan horses.

However, if you choose to deny this content type, many Web pages can no longer be displayed on browsers within your network. The reasons for this include, but are not limited to, the following:
  • On the Web server, not all used content is encoded with the expected content type (for example, some servers deliver JavaScript files or style sheets as application/octet-stream instead of application/x-javascript and text/css. If you deny the application/octet-stream content type, none of these files can be downloaded to the browser, and therefore the affiliated Web pages cannot be displayed correctly.
  • The server uses "http 301" or "http 302" responses to redirect the user to a different page. Some Web servers encode these 301 and 302 responses with the application/octet-stream content type (instead of text/html, as one might expect). If you deny the application/octet-stream content type, this redirection will no longer work.
For these reasons, it is not recommended that you deny the application/octet-stream content type on a general basis.

Article ID: 319073 - Last Review: 03/04/2014 05:28:37 - Revision: 1.1

Microsoft Internet Security and Acceleration Server 2000 Standard Edition

  • kbnosurvey kbarchive kbinfo kbisa2004yes KB319073