This documentation is archived and is not being maintained.


Exchange Server 2003


This content is no longer actively maintained. It is provided as is, for anyone who may still be using these technologies, with no warranties or claims of accuracy with regard to the most recent product version or service release.

Term Definition

absolute URL

A URL that has the full address necessary for locating a resource in an Exchange store.

access control entry

An individual item in an access control list (ACL). Every user or group object that has rights to access an Exchange store resource is listed in the ACL for a resource as an ACE.

access control list

A listing for an Exchange store resource that indicates which users and groups have access permissions. Individual entries in the list are known as access control entries (ACEs).

access mask

A 32-bit number in which the upper 16 bits define standard and generic access rights and the lower 16 bits define access rights that are specific to the folder or item.

action table

A set of rules, stored as an ADO Recordset, that define how workflow items can change state. Each row in an action table represents a possible state transition in the workflow.


A workflow task detailing how an item moves from state to state or executes script. Multiple actions can be associated with a particular state.

Active Directory Service Interfaces (ADSI)

A dual-interfaced model that allows programmatic access to underlying directory services through a common command set. Active Directory Service Interfaces is dual-interfaced in that it extends the IDispatch interface and provides access to defined methods through the v-table and through the seven methods defined by the IDispatch interface.

Active Directory

The directory service for Microsoft Windows 2000 Server. It stores information about objects on the network and makes this information available for authorized administrators and users. Active Directory gives network users access to permitted resources anywhere on the network using a single logon process. It provides administrators with an intuitive hierarchical view of the network and a single point of administration for all network objects."

ActiveX Data Objects (ADO)

A collection of data access objects in a hierarchical object library. ActiveX Data Objects enables you to write a client application to access and manipulate data in a database server through a provider (database interface) such as Microsoft Internet Information Server (IIS 4.0).


Active Server Pages (ASP) is the server-side scripting environment of Microsoft Internet Information Services (IIS) that can be used to build interactive high-performance Web-based applications using HTML pages, server-side scripts, and ActiveX components.

asynchronous event

A type of event that fires after a change has been fully committed to the Exchange store. Asynchronous events do not block the Exchange store thread but instead fire after the action has been committed.


A person invited to attend a meeting or appointment. An attendee can accept, decline, or ignore a meeting request. Represented by the Collaboration Data Objects (CDO) Attendee object.


In object-oriented programming, a generalized category that describes a group of more specific items, called objects, which can exist within it. A class is a descriptive tool used in a program to define a set of attributes or a set of services that characterize any member (object) of the class.

Collaboration Data Objects (CDO)

An application programming interface that allows users and applications high-level access to data objects in Exchange. Collaboration Data Objects (CDO) defines the concept of different object classes, including messages, posts, appointments, and tasks.


An array of objects of a similar type or class.


A contact is an Active Directory object that contains information about an individual such as name, address, and job title. It can include a foreign e-mail address. A contact in Exchange 2000 is equivalent to a custom recipient in earlier versions of Exchange. The Contact object is derived from the Person class but it is not a security principal and therefore cannot log onto the network or access any Exchange resources.

content class

A name identifying the intent or purpose of an item. Content class determines which Exchange store schema properties are associated with a resource when it is created.

distinguished name (DN)

An identifier for an object that is unique across the entire Active Directory. The name identifies the domain that holds an object as well as the complete path through the container hierarchy used to access the object. Earlier versions of Exchange used a distinguished name format that referenced an Exchange mailbox.

Domain Name System (DNS)

A widely used standards-based protocol that allows clients and servers to resolve names into IP addresses and vice versa.

dynamic-link library (DLL)

An operating system feature that allows executable routines (generally serving a specific function or set of functions) to be stored separately as files with .dll extensions. These routines are loaded only when needed by the program that calls them.

event registration item

A hidden item that contains the ProgID of an event sink, information about what events will trigger the event sink, and options that tell when or under what conditions the event sink will be triggered. The event registration item is created in the same folder that is being monitored for events.

event registration

An item residing in a folder that uses an event sink. The item provides the store with information that includes what events will trigger the sink, the name of the sink, and options such as restrictions for when the event will fire. The event registration item can be created with either Microsoft ActiveX Data Objects or with a special script tool that can be used in batch files known as RegEvent.

event sink

Code that gets activated through a defined trigger, such as the receipt of a new message. The code is normally written in any COM-compatible programming language, such as Microsoft Visual Basic, Microsoft Visual Basic, Scripting Edition, JScript, and C/C++. Exchange supports transport, protocol, and store event sinks. Event sinks on the store can be synchronous (code executes as the event is triggered) or asynchronous (code executes sometime after the event).


The occurrence of some particular action or the occurrence of a change of state that can be handled by an event sink. For example, the arrival of a message to the Simple Mail Transport Protocol (SMTP) service is an event that can be handled by a number of event sinks.


A specific appointment that is added, modified, or deleted from the pattern of a recurring appointment or meeting.

Exchange store schema

The data definition of a single Exchange store used to define all of the resources, such as folders, items, and Web files, found in the store. The schema consists of a large number of predefined schema properties, which determine the qualities, such as the creation date or the display name, of a resource.

Exchange store

A storage platform that provides a single repository for managing multiple types of unstructured information in one infrastructure. The Exchange store combines the features and functionality of the file system, the Web, and a collaboration server (such as Microsoft Exchange) through a single, URL-addressable location for storing, accessing, and managing information, as well as building and running applications. The Exchange store is also known as the Web Storage System.

Exchange System Manager

In Exchange 2000 Server, the Exchange Administrator has been replaced by the Exchange System Manager. The Exchange System Manager is a collection of Microsoft Management Console (MMC) snap-ins that Exchange 2000 Server provides to MMC.

folder tree

A hierarchy of folders in the Exchange store very similar in structure to the standard file system. A single folder can contain child folders, which, in turn, can contain other child folders.

free/busy status

The availability of a person. In addition to free and busy, the status can also be out of office (OOF) or tentative.

Global Address List (GAL)

A list of users and other objects in a directory that Outlook users can access to view information about those users and objects. In a hosting (shared) environment, the customer GAL is a list of objects that a customer is allowed to see. Permissions can be set on GALs so that certain customer data is isolated from other customers in a shared environment.

global domain identifier (GDI)

Specifies the country/region, the administration management domain (ADMD), and the private management domain (PRMD) of an X.400 e-mail address. For example c=us; a=MCI; p=msft.


Hypertext Transfer Protocol (HTTP) is an Internet standard protocol that lets Web browsers like Microsoft Internet Explorer access Exchange stores. WebDAV is an extension to HTTP that you can use to build applications that are writable instead of just read-only.


An encapsulated set of properties and methods, some of which are specific to certain classes, while others define a common functionality. By encapsulating properties and methods in this way, interfaces can be easily shared among predefined and custom classes.

LDAP Data Interchange Format Data Exchange (LDIFDE)

LDIFDE is a utility program included in Windows 2000 that supports batch operations such as add, create and modify, and that uses files based on the LDIF standard. LDIF is an Internet standard for a file format that can be used to perform batch import and export operations on LDAP directories such as Active Directory.


Lightweight Directory Access Protocol (LDAP) is the standard Internet protocol used for directory access. LDAP is the wire protocol used to conduct conversations between a client application and Active Directory across the network. An LDAP application can access any directory service that exposes an LDAP protocol. The LDAP client library (WLDAP32.dll) is installed with all versions of Microsoft Windows 2000.

mailbox store

A database for storing mailboxes in Exchange. Mailbox stores store data that is private to an individual and contain the mailbox folders generated when a new mailbox is created for an individual.

mail-enabled object

A type of object that has an e-mail address on a domain in the organization, but the object does not have a mailbox in the domain at which to receive messages. The object appears in the global address list, which allows other people in the organization to easily locate or send a message to that person, but the administrator does not need to manage an unnecessary mailbox. Contacts, users, and even folders can be mail-enabled.

message transfer agent (MTA)

The component of all versions of Exchange Server that transfers messages between servers using the X.400 protocol.

message transfer envelope (MTE)

A MAPI message that holds the delivery information for a message. The MTE includes the addressing properties for each recipient, header information such as the sender and subject, and specifications for responding and exception handling. It encloses another MAPI message that contains the contents of the message to be delivered. MTEs are only created in gateway folders. In contrast, regular user folders contain the message contents only.

message transfer system (MTS)

The X.400 term for a messaging system, which is a product that enables electronic communication over a network.

Messaging Application Programming Interface (MAPI)

A messaging architecture enabling multiple applications to interact with different messaging systems across a variety of hardware platforms. MAPI is built on the COM architecture.

Microsoft Management Console (MMC)

A management display framework that hosts administration tools and applications. Using MMC, you can create, save, and open collections of tools and applications. Saved collections of tools and applications are called consoles.

MIME Encapsulation of Aggregate HTML Documents (MHTML)

An Internet standard that defines the MIME structure used to send HTML content in message bodies along with those elements used in a Web page.


A logical collection of properties in an Exchange store schema. A namespace serves to group related properties together for easy property discovery and, more importantly, to keep the property names unique.

Network News Transfer Protocol (NNTP)

An Internet standard protocol used across Transmission Control Protocol/Internet Protocol (TCP/IP) networks for accessing newsgroups through an NNTP-compatible client such as Microsoft Outlook Express. You can use NNTP to build online discussions and set up newsgroup applications.

offline address book (OAB)

A copy of an address book that has been downloaded so that an Outlook user can access the information it contains while disconnected from the server.


Something that happens only once, or which is instantiated only once.

Post Office Protocol (POP) version 3

An Internet standard protocol that allows a user to download e-mail from his or her inbox on a server to the client computer where messages are managed. This protocol works well for computers that are unable to maintain a continuous connection to a server.

public store

A database for storing public folders in Exchange. A public store can be accessible to everyone in an organization or can be restricted to a subset of individuals such as a department or team.

recipient policy

A policy applied to mail-enabled objects to generate e-mail addresses. Recipient policies can be defined to apply to thousands of users, groups, and contacts in Microsoft Active Directory by using a Lightweight Directory Access Protocol (LDAP) query interface in a single operation.

Recipient Update Service (RUS)

An Exchange 2000 service that updates the recipient objects within a domain with specific types of information. You can schedule appropriate intervals to update the recipient objects. For example, the RUS updates recipient objects with address list membership and e-mail addresses at intervals scheduled by the administrator.

recursive event

An event that can be registered for a parent folder as well as for any child folders.

relative URL

A URL that contains only a partial address and uses an absolute URL as a reference point for navigating in a hierarchy.

remote procedure call (RPC)

A protocol standard used to write routines that send information in packet format over the network.


Anything placed in the Exchange store. A resource can be an e-mail message, an appointment, another folder, a Web page, or any structured document such as a Microsoft Excel spreadsheet.

security descriptor

A descriptor containing information about the security attributes for an Exchange store resource including a list of users and groups that have access permissions to the resource.

security identifier (SID)

A value that identifies the user or group object being granted or denied access rights. The SID of a user or group object identifies the specific access control entry (ACE).

security principal

An object that can be granted and denied rights to access resources on the network.


The logic that serves as the underpinning of programming syntax. A program that is syntactically correct can be semantically incorrect.


Simple Mail Transfer Protocol (SMTP) is an industry standard for Internet e-mail delivery. This is the native protocol that Exchange uses to transfer messages.


A Microsoft Management Console (MMC) extension. A snap-in is used to manage services for a component or product.


The status of an item in a workflow process. As an item moves through a workflow process, it assumes different states. You use an item's state to track its progress through a workflow process. A state can have multiple actions associated with it.

storage groups

Groups created with Exchange System Manager that are used to organize multiple Exchange stores into more manageable units in Exchange. Used primarily for building or returning and setting mailbox settings stored in Active Directory. The name of a storage group is not needed to access the contents of a mailbox or of a public Exchange store.


Technology used by Exchange to store user mailboxes and folders. There are two kinds of stores: mailbox stores and public stores. A store consists of a rich-text database (.edb), plus a streaming native Internet content database (.stm).

synchronous events

Events that fire immediately before an item is committed to the Exchange store. These events block the Exchange store thread until the event thread has finished executing. While executing, a synchronous event has exclusive control over the item that triggered the event. No other process or request can access the item until the event sink is finished executing.

system events

Events that are not tied to any particular item or folder in the Exchange store. Instead, they are associated with general actions such as the starting of a database or the system clock reaching a certain time. Within their context, they behave as asynchronous events and do not fire until after the Exchange store has completed the action triggering the event.


A set of independent operations that are bundled together and performed as an atomic operation; the operations succeed or fail as a whole.

Universal Time Coordinate (UTC)

A universal timekeeping standard based on Greenwich Mean Time (GMT). Local time is calculated in UTC and offset by the local time zone.

virtual directory

A name used to access the contents of any Exchange store using a Web browser. The virtual directory name is used to open a mailbox as well as browse the folders of a public store. This name is also used in URLs using the Microsoft Internet Publishing Provider (MSDAIPP), which includes both hyperlinks in Web pages as well as Microsoft ActiveX Data Objects client-side code.

Web-Based Enterprise Management (WBEM)

An initiative undertaken by the Distributed Management Task Force (DMTF) to provide enterprise system managers with a standard solution for management. Windows Management Instrumentation (WMI) is the Microsoft implementation of the WBEM initiative for Windows operating systems.

WebDAV protocol

The World Wide Web Distributed Authoring and Versioning (WebDAV) protocol can be used to access items in an Exchange store. It provides a means to access not only the contents of an item but also an extensible set of associated properties. Also known as the HTTP/DAV or DAV protocol.

Windows Management Instrumentation (WMI)

Windows Management Instrumentation (WMI) is the Microsoft implementation of Web-Based Enterprise Management (WBEM), which is an industry initiative to develop a standard technology for accessing management information in an enterprise environment. WMI uses the Common Information Model (CIM) industry standard to represent systems, applications, networks, devices, and other managed components in an enterprise environment.

workflow engine

An in-process server (CDOWF.DLL) that implements the IProcessInstance Advance method.


Server-side logic that you can use to route items in a folder from one user to another and enforce and track an item throughout its lifetime.


An international messaging standard that can be used by a variety of messaging systems. X.400 uses a strict addressing method that reflects a hierarchical environment. The use of X.400 has been largely supplanted by the combination of SMTP and MIME.


Extensible Markup Language (XML) is a tag language based on Standard Generalized Markup Language (SGML) that is optimized for delivery over the World Wide Web. XML defines data layout for a document but not display characteristics, which are commonly defined using HTML. It permits data to be manipulated using HTTP, WebDAV, and Extensible Style Language (XSL) among different applications on different platforms. XML is not required to conform to the HTML specification.