DOCUMENT:Q191558  14-APR-1999  [exchange]
TITLE   :XADM: POP3 Secure Password Authentication
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 
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SYMPTOMS
========

Mail can not be downloaded or viewed using Microsoft Outlook Express Secure
Password Authentication (SPA) to access messages on an Exchange Server computer.
You may receive the following error message:

   You could not be logged on to the mail server using Secure Password
   Authentication. Please check your account information and verify that
   your mail server supports Secure Password Authentication.

This functionality requires that Exchange Server has the Windows NT
Challenge/Response enabled for the POP3 protocol.

CAUSE
=====

This problem may occur when a client using SPA tries to log on to a mailbox
where the mailbox alias is different than the Windows NT account. The mail
client uses the computer's logon credential information for SPA and assumes that
the mailbox alias will be the same as the Windows NT account.

WORKAROUND
==========

Change the users mailbox alias to match the Windows NT account in the Exchange
Server Administrator program.

MORE INFORMATION
================

You can test this by telneting to port 110 of the server. After you receive the
server's "ready" response from the Exchange Server computer, type "Auth NTLM,"
(without the quotation marks) and CRLF. If you get "+ OK," then the server
supports Secure Password Authentication. Otherwise, you will receive "The NTLM
Authentication package has been disabled for this protocol."

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Keywords          :  
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : WINDOWS:4.0,5.0,5.5

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