DOCUMENT:Q166225  09-MAY-1999  [exchange]
TITLE   :XWEB: Err Msg: Requested Header Not Found
PRODUCT :Microsoft Exchange
PROD/VER:WinNT:5.0
OPER/SYS:
KEYWORDS:kbusage

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The information in this article applies to:

 - Microsoft Exchange Server, version 5.0 
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SYMPTOMS
========

When you attempt to access a mailbox on a Microsoft Exchange Server computer by
way of the Web, you may receive the following error message:

   Internet Explorer cannot open the Internet site
   http://<server>/exchange/LogonFrm.asp?Mailbox=<alias>.
   The requested header was not found.

NOTE: <server> is the name of the server running Internet Information
Server (IIS) and the Active Server Components, and <alias> is the alias of
the Exchange Server mailbox you are attempting to sign in from.

CAUSE
=====

This error will occur if the only password authentication configured for IIS is
Allow Anonymous.

RESOLUTION
==========

To resolve this problem:

 - To log on to an Exchange mailbox, you must have either Basic (Clear Text)
   and/or Windows NT Challenge/Response Authentication on the computer running
   IIS. This is required in order to allow IIS to pass your user credentials on
   to a computer running Exchange Server.

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Keywords          : kbusage 
Technology        : kbExchangeSearch kbExchange500 kbZNotKeyword2
Version           : WinNT:5.0

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