DOCUMENT:Q297210 13-JUN-2001 [iis] TITLE :Using Challenge Response on a Web Site that Has Framesets PRODUCT :Internet Information Server PROD/VER::4.0,5.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Information Server versions 4.0, 5.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you use frameset pages on a site that uses NT Challenge Response as the only authentication method, 401 errors may appear in the IIS logs during the user's session. The user can successfully access the file shortly after the errors occur, and may experience slight delays in accessing some files. CAUSE ===== When Microsoft Internet Explorer attempts to open a page that is divided into multiple frames, it requests the different frames pages simultaneously on separate ports. IIS sees these as separate requests because they are coming in on separate ports, and requires each request to be authenticated individually. MORE INFORMATION ================ This is by design for security reasons. Allowing the subsequent sockets to be opened without requiring authentication first leaves the server open to attack. Additional query words: IIS IE 401 frame NTLM ====================================================================== Keywords : Technology : kbiisSearch kbiis500 kbiis400 Version : :4.0,5.0 Issue type : kbprb Solution Type : kbpending ============================================================================= 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 2001.