DOCUMENT:Q248020 31-JUL-2001 [iis] TITLE :IIS 5.0: Err Msg "HTTP/1.1 407 Proxy Authentication Required" PRODUCT :Internet Information Server PROD/VER:winnt:5.0 OPER/SYS: KEYWORDS:kbOSWin2000 kbiis500 kbiis500prod2web kbhttp407 kbProd2Web ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Information Services version 5.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you attempt to connect to a Web site through proxy server, the following error may appear: HTTP/1.1 407 Proxy Authentication Required You must authenticate with a proxy server before this request can be serviced. Please logon to your proxy server and then try again. CAUSE ===== This error is returned when you try to access a Web site through a proxy server that has access control turned on while using Basic Authentication. The Web Proxy, through a 407 HTTP response, requests credentials from the browser client (or downstream Proxy Server). The client provides the credentials, or in the case of a downstream Web proxy, the proxy server may provide the credentials itself. If the credentials used by the client or by the downstream proxy server are not allowed by the upstream proxy server, this error will be displayed. RESOLUTION ========== This can be resolved by passing the correct credentials to the proxy server. Contact the administrator of the proxy server and verify that the account has permission to use the proxy server. WORKAROUND ========== You can also use the following workaround to resolve this issue: - Enable "Anonymous" authentication on the proxy server computer. Additional query words: IIS 5 HTTP/1.1 407 ====================================================================== Keywords : kbOSWin2000 kbiis500 kbiis500prod2web kbhttp407 kbProd2Web Technology : kbiisSearch kbiis500 Version : winnt:5.0 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 2001.