DOCUMENT:Q231453 11-JUN-2002 [iis] TITLE :Internet Explorer 5.0 Fails to Pass Session Variables to IIS PRODUCT :Internet Information Server PROD/VER::4.0,5 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Explorer version 5 for Windows NT 4.0 - Microsoft Internet Information Server version 4.0 ------------------------------------------------------------------------------- IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base: Q256986 Description of the Microsoft Windows Registry SYMPTOMS ======== When you attempt to post a form through ASP to a Microsoft IIS 4.0 computer with Internet Explorer 5.0 and session variables used in the POST to the server, the session variables may not display in the browser, as in previous versions of Internet Explorer . CAUSE ===== Internet Explorer 5.0 has added a feature called NTLM pre-authorization. When an Internet Explorer 5.0 browser connects to an IIS 4.0 Web site that uses NTLM security, Internet Explorer 5.0 negotiates security. If an NTLM challenge is received, these credentials are used for any subsequent request for that Web site. In this case, when an Internet Explorer 5.0 browser connects, it receives an NTLM challenge, but when a sub folder on the same Web site does not use NTLM, no challenge is received by Internet Explorer 5.0, which causes the browser to not send the POST data to the server. RESOLUTION ========== WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk. 1. Start Registry Editor (Regedt32.exe). 2. Locate the following key in the registry: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\InternetSettings 3. On the Edit menu, click Add Value, and then add the following registry value: Value Name: DisableNTLMPreAuth Data Type: REG_DWORD Value: 1 4. Quit Registry Editor. STATUS ====== Microsoft has confirmed this to be a problem in the Microsoft products that are listed at the beginning of this article. MORE INFORMATION ================ This problem only occurs when you use Internet Explorer to connect to an IIS 4.0 computer where NTLM security is placed on the parent virtual directory and anonymous security is placed on any sub directory below the parent directory. Additional query words: preauth ====================================================================== Keywords : Technology : kbiisSearch kbIEsearch kbiis400 kbZNotKeyword2 kbIENT400Search kbIE500Search kbZNotKeyword3 kbIE500WinNT400 Version : :4.0,5 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.