Internet Explorer May Lose the First 2,048 Bytes of Data That Are Sent Back from a Web Server That Uses HTTP Compression

This article was previously published under Q312496
This article has been archived. It is offered "as is" and will no longer be updated.
Internet Explorer may lose the first 2,048 bytes of data that are sent back from a Web server that uses Hypertext Transfer Protocol (HTTP) compression. This problem occurs if a program has registered a namespace handler for any of the following protocols:
One example of such a program is the Real Download software (which is available in a full installation of Real Player Basic). This program registers namespace handlers for HTTP and FTP. The data loss may manifest itself in script errors or incorrectly displayed HTML elements.
The behavior is caused by a problem in Urlmon.dll. The problem occurs when Urlmon.dll binds specifically to notify programs that have registered namespace handlers. The problem occurs if any of the following registry keys is present:
  • HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\http
  • HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\ftp
  • HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\gopher
  • HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\https
  • HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\file
Real Download 8 registers the following keys :
  • [HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\ftp\RealDownload]
  • [HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler\http\RealDownload]
To resolve this problem, obtain the latest service pack for Internet Explorer 6. For additional information, click the following article number to view the article in theMicrosoft Knowledge Base:
328548 How to Obtain the Latest Internet Explorer 6 Service Pack
The English version of this fix should have the following file attributes or later:
   Date         Time   Version       Size     File name   -----------------------------------------------------   08-Jan-2002  11:56  6.0.2713.800  480,256  Urlmon.dll				

To work around this problem, use any of the following methods:
  • Disable HTTP compression by changing the Web server's configuration.
  • Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
    322756 How to back up and restore the registry in Windows

    Delete any of the registry keys that are listed earlier in this article in the HKEY_CLASSES_ROOT\PROTOCOLS\Name-Space Handler key. Note that using this method this prevents the program that registered the namespace handler from working as you expect.
  • Remove the program that registered the namespace handler for one of the protocols that is listed earlier in this article.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Internet Explorer 6 Service Pack 1.
The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

Article ID: 312496 - Last Review: 12/07/2015 08:10:22 - Revision: 3.11

Microsoft Internet Explorer 6.0

  • kbnosurvey kbarchive kbhotfixserver kbqfe kbbug kbfix kbie600presp1fix kbie600sp1fix KB312496