A GET Request After a POST Request Does Not Work If There Is an Extra CRLF in the Content

If a Web browser or a similar client that uses the Internet Security and Acceleration (ISA) Server Web Proxy service sends a request (such as a GET or similar request) immediately after a POST request that contains an extra pair of 0d0a bytes (0x0d 0x0a, or CRLF), that request does not succeed and returns HTTP error 400.

Note that the ISA Server Web Proxy service ignores the extra bytes in the POST request in the outbound direction only if you have applied the hotfix that is described in the following Microsoft Knowledge Base article: Without the hotfix, and in the inbound direction, ISA Server rejects all requests in which the content length is different from the length that is specified in the "Content length" HTTP header. Without the hotfix, the POST request also may not succeed.

To resolve this problem, obtain the latest service pack for ISA Server 2000. For additional information about the latest service pack, click the article number below to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

This problem was corrected in ISA Server 2000 SP1.