Unicode and character sets in Exchange 2000 Server

This article discusses Unicode and how it is used in Exchange 2000.

Introduction to Unicode

Unicode is a character coding system that is designed to represent characters in a numeric manner. Each character is represented by a single number that is consistent across platforms, programs, and languages. By using Unicode, a single software product can support multiple languages and platforms without being re-engineered.

Unicode is an International Standards Organization (ISO) character set (ISO number 10646). It includes roughly 40,000 characters or ideographs that represent most of the languages that are written today.

For additional information about Unicode, visit the Unicode Web site:Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.

About Unicode in Active Directory

Microsoft Windows 2000 Active Directory objects (for example, user, contact, and group) accept Unicode characters for almost every property. For example, the Display Name in the Address Lists property and the Common Name property can contain Unicode characters. These server-side properties permit most characters; however, some clients may not display them or handle them properly.

Microsoft Windows 2000 MultiLanguage Version, which is available separately from Windows 2000, extends the native language support in Windows 2000 and permits the user interface languages to be changed for each user.

Note The Windows 2000 MultiLanguage Version is available only to customers in the Microsoft Open License, Select License, and Enterprise Agreement programs.

For more information about Microsoft licensing programs, visit the following Microsoft Web site: For more information about using Unicode with Exchange 2000 and Active Directory, click the following article number to view the article in the Microsoft Knowledge Base:

About Unicode in Exchange 2000

Exchange 2000 stores most message content as Unicode. Exchange 2000 stores the character set information with the message content. This content can have multiple languages and can therefore have multiple language tags in the Exchange 2000 store.

Special characters in administrative group names

When working with administrative group names, Exchange 2000 does not support extended characters in server objects (for example, server name), but does support teletext characters (CODEPAGE 20261,T.61). Unicode and double-byte character set (DBCS) strings are acceptable, as are embedded spaces and hyphens.

Exchange 2000 Setup and Exchange System Manager enforce these naming rules for new installations of Exchange 2000 and for upgrades from Exchange Server 5.5. If you upgrade an Exchange server to Exchange 2000 and you have an organization or site name that contains any of these characters, you must change the display name before you run Exchange 2000 Setup. Avoid special characters if possible.

In Exchange 2000, the name of an Exchange 2000 organization and its administrative groups cannot contain any of the following special characters:

Character	Character name
~	tilde
{	opening brace
`	apostrophe
[	opening square bracket
!	exclamation point
}	closing brace
@	at sign
]	closing square bracket
#	pound or number sign
|	pipe
$	dollar sign
\	backward slash
%	percent
:	colon
^	carat
;	semicolon
&	ampersand
_	underscore
.	period
?	question mark
/	forward slash
,	comma
"	double quotation mark
*	asterisk
'	single quotation mark
(	opening parenthesis
)	closing parenthesis
<	less then
>	greater than
+	plus sign
=	equal sign

Special characters in Exchange user objects

The alias property of user objects can only contain US-ASCII characters, the first 128 characters of almost all character pages, and extended ASCII characters. All accented characters and symbols for Western European languages are permitted and all high-ASCII characters, such as Russian or Japanese characters, are excluded.

Active Directory permits user names to contain Unicode characters. You may have to use Unicode characters to create a user name that matches the user's name in their native language. User names can contain high-ASCII or DBCS characters.

Unicode characters in the user name may make it difficult to log on to Microsoft Outlook Web Access (OWA). When users log on to OWA, they must type their domain name, user name, and password. The user name must be provided in US-ASCII characters. When Internet Information Services (IIS) 5.0 was released, there was no Internet standard for encoding non-US-ASCII characters in HTTP authentication. Future versions of Microsoft Internet Explorer and IIS will use UTF-8 to encode this data, thereby permitting any Unicode character in the user name.

You can also configure OWA to use User Principle Names (UPN). For more information about using OWA with UPN, click the following article number to view the article in the Microsoft Knowledge Base:

SMTP naming considerations

When connecting to the Internet and other SMTP systems, consider any character restrictions that are imposed by SMTP addressing schemes. Uppercase and lowercase letters are permitted because no distinction is made between these characters. The numbers 0 through 9 and hyphens are also permitted, but SMTP addresses cannot contain spaces. Note that the default SMTP address format is someone@example.com.