DOCUMENT:Q248085  31-JUL-2001  [iis]
TITLE   :Err Msg: HTTP 401.5 - Unauthorized: Authorization by ISAPI ...
PRODUCT :Internet Information Server
PROD/VER:winnt:4.0,5.0
OPER/SYS:
KEYWORDS:kbOSWin2000 kbiis500prod2web kbhttp4015 kbProd2Web

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The information in this article applies to:

 - Microsoft Internet Information Services version 5.0 
 - Microsoft Internet Information Server 4.0 
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SYMPTOMS
========

When you attempt to access an IIS Web site, the following error message may
occur:

   HTTP 401.5 - Unauthorized: Authorization by ISAPI or CGI application failed

CAUSE
=====

The Web address has an ISAPI (Internet Server Application Programming Interface)
or CGI (Common Gateway Interface) program that verifies user credentials. The
authentication credentials used to connect to the server were denied access by
this program.

RESOLUTION
==========

To resolve this issue, attempt to access the server again using the appropriate
credentials. Contact the system administrator to obtain the correct logon
information.

Additional query words: IIS 5

======================================================================
Keywords          : kbOSWin2000 kbiis500prod2web kbhttp4015 kbProd2Web 
Technology        : kbiisSearch kbiis500 kbiis400
Version           : winnt:4.0,5.0
Issue type        : kbprb
Solution Type     : kbpending

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