DOCUMENT:Q272492  08-MAY-2002  [winnt]
TITLE   :POP3 and IMAP Clients Are Not Authenicated on Exchange Server
PRODUCT :Microsoft Windows NT
PROD/VER::4.0,4.0 SP6a
OPER/SYS:
KEYWORDS:kbWinNT400PreSP7Fix

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The information in this article applies to:

 - Microsoft Windows NT Server versions 4.0, 4.0 SP6a 
 - Microsoft Windows NT Server, Enterprise Edition versions 4.0, 4.0 SP6a 
 - Microsoft Windows NT Workstation versions 4.0, 4.0 SP6a 
 - Microsoft Exchange 2000 Server 
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SYMPTOMS
========

When the Exchange Server 2000 registry key
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\LSA has the
LmCompatibilitylevel value set to 5, POP3 and IMAP clients are not
authenticated.

CAUSE
=====

This issue occurs because the 5 value does not allow a check for clear text
passwords, and authentication therefore does not work properly.

RESOLUTION
==========

A supported fix is now available from Microsoft, but it is only intended to
correct the problem described in this article and should be applied only to
systems experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the
fix. For a complete list of Microsoft Product Support Services phone numbers and
information on support costs, please go to the following address on the World
Wide Web:

   http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are normally incurred for support calls may
be canceled, if a Microsoft Support Professional determines that a specific
update will resolve your problem. Normal support costs will apply to additional
support questions and issues that do not qualify for the specific update in
question.

The English version of this fix should have the following file attributes or
later:

   Date         Time   Size     File name     Platform
   ---------------------------------------------------
   25-Sep-2000  21:07  247,056  Advapi32.dll  x86
   25-Sep-2000  21:08   48,400  Msv1_0.dll    x86

   25-Sep-2000  21:06  403,728  Advapi32.dll  Alpha
   25-Sep-2000  21:06   79,632  Msv1_0.dll    Alpha



STATUS
======

Microsoft has confirmed this to be a problem in Windows NT 4.0.

Additional query words: 4.00

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Keywords          : kbWinNT400PreSP7Fix 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400sp6 kbWinNTS400search kbWinNTS400 kbExchangeSearch kbExchange2000Search kbWinNTSEnt400SP6a kbWinNTW400SP6a kbExchange2000Serv
Version           : :4.0,4.0 SP6a
Hardware          : ALPHA x86
Issue type        : kbbug
Solution Type     : kbfix

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