DOCUMENT:Q324025  06-AUG-2002  [exchange]
TITLE   :XCON: POP3 & IMAP4 Clients Can't Log On, Event ID 13003 Occurs
PRODUCT :Microsoft Exchange
PROD/VER::5.5
OPER/SYS:
KEYWORDS:kberrmsg

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Exchange Server, version 5.5 
-------------------------------------------------------------------------------

SYMPTOMS
========

Post Office Protocol 3 (POP3) and Internet Message Access Protocol, Version
4rev1 (IMAP4) clients may not be able to log on to Exchange 5.5 Server.
Additionally, an event similar to the following is recorded in the application
event log:

   Event ID: 13003
   Event Type: MSExchangePOP3
   Event Source:
   Event Category: Authentication
   Description:

   Hr lookup credentials () call failed with error logon failure. Unknown user
   name or bad password.

CAUSE
=====

This behavior may occur if the Exchange Server mailbox alias is different from
the Microsoft Windows user account name.

RESOLUTION
==========

To resolve this issue, use one of the following methods, as appropriate to your
situation:

 - Use the following format for the user account name on the client, where
   <Domain> is the name of the domain, <UserName> is the Windows
   user account name, and <Mailbox> is the Exchange Server mailbox alias:

   <Domain\UserName\Mailbox>

-or-

 - Change the Exchange Server mailbox alias to use the same name as the Windows
   user account name. By doing so, users require only one account name.

NOTE: The <Domain\UserName\Mailbox> format is used by and works with
Microsoft Outlook Express clients. Results may vary with other clients.

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

For additional information about how to troubleshoot a similar issue, click the
article numbers below to view the articles in the Microsoft Knowledge Base:

   Q236032 OLEXP: Outlook Express and Outlook Repeatedly Prompt You for Your
   Password

   Q199274 XCON: Event 13005 During POP3 Logon

Additional query words: front page

======================================================================
Keywords          : kberrmsg 
Technology        : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version           : :5.5
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 2002.