Error message when you try to access a Web site from a Web browser client that is located behind a computer that is running ISA Server 2004 with SP2: "Error Code: 502 Proxy Error"

When you try to access an external Web site from a Web browser client that is located behind a computer that is running Microsoft Internet Security and Acceleration (ISA) Server 2004 with Service Pack 2 (SP2), you may receive an error message that is similar to the following:

This problem occurs because ISA Server 2004 SP2 ignores the response from the Web server if the response contains both the Content-Length header and the Transfer-Encoding header.

To resolve this problem, obtain the update for HTTP issues in Internet Security and Acceleration Server 2004 with SP2. For more information about this update, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information about the description of the standard terminology that is used to describe Microsoft software updates, click the following article number to view the article in the Microsoft Knowledge Base: