DOCUMENT:Q184226  09-APR-1999  [exchange]
TITLE   :XADM: How Advanced Security Works on a Mailbox
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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SUMMARY
=======

Microsoft Exchange Server supports three encryption algorithms: CAST-64, DES,
and CAST-40. The level of encryption is determined by the Exchange and/or
Outlook client, not the server. The U.S./Canada version of all Microsoft
Exchange Client products supports all three algorithms, but defaults to CAST-64.
All other international (localized) versions of Exchange Client support only the
CAST-40 (40 bit) algorithm.

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

When you are using a CAST-64 or DES client, Exchange sends the message based on
the encryption information in the mailbox or individual mailboxes that it is
sending to. The CAST-64 and DES clients can read all encrypted mail.

When you are using a CAST-40 client, the directory for that mailbox is updated so
that other users will send only 40-bit encryption. While you are logged on to
the CAST-40 client, you can not read messages encrypted with CAST-64 or DES
encryption.

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

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