Upgrading from Mixed Exchange 2000 and Exchange 5.5 Organizations

 

This topic provides instructions for upgrading from a mixed Microsoft® Exchange 2000 Server and Exchange Server 5.5 organization to an Exchange Server 2003 organization. Furthermore, because it is recommended that you run your new Exchange Server 2003 organization in native mode, this topic discusses the advantages of native mode and provides instructions for switching from mixed mode to native mode.

Specifically, this topic will:

  • Provide you with the information necessary to upgrade your Exchange 2000 Server and Exchange Server 5.5 organization to Exchange Server 2003.

  • Provide you with information about running Exchange Server 2003 Deployment Tools.

  • Show you how to use the Active Directory Tool.

  • Show you how to run ForestPrep.

  • Show you how to run DomainPrep.

  • Show you how to upgrade your Exchange 2000 Servers to Exchange Server 2003.

  • Provide you with the information necessary to install a new Exchange Server 2003 server.

Note

You can install a new Exchange Server 2003 server before upgrading your existing Exchange 2000 Servers. It is not necessary that you perform the upgrade first.

  • Provide you with the information necessary to migrate your Exchange Server 5.5 mailboxes and public folders to Exchange Server 2003.

  • Provide you with information about how to switch your Exchange organization from mixed mode to native mode.

Permissions for Upgrading from Mixed Exchange 2000 Server and Exchange 5.5 Organizations

After ensuring that your organization meets the necessary prerequisites, the procedures referenced in this topic guide you through the deployment process.

Table 1 lists the required permissions or roles for the procedures referenced in this topic.

Table 1   Procedures referenced in this topic and corresponding permissions

Procedure Required permissions or roles

Enable Microsoft Windows® 2000 Server or Microsoft Windows Server™ 2003 services

  • See Windows 2000 or Windows Server 2003 Help

Run ForestPrep on a domain controller (updates the Microsoft Active Directory® directory service schema)

  • Enterprise Administrator

  • Schema Administrator

  • Domain Administrator

  • Local Machine Administrator

Run DomainPrep

  • Domain Administrator

  • Local Machine Administrator

Install Active Directory Connector (ADC)

  • Enterprise Administrator

  • Schema Administrator

  • Domain Administrator

  • Local Machine Administrator

Install Exchange 2003 on the first server in a domain

  • Exchange Full Administrator role applied at the organization level

  • Exchange 5.5 Administrator under the organization, site, and configuration nodes (if installing into an Exchange 5.5 site)

  • Local Machine Administrator

Install Exchange 2003 on additional servers in the domain

  • Exchange Full Administrator role applied at the administrative group level

  • Exchange 5.5 Site Administrator (if installing into an Exchange 5.5 site)

  • Local Machine Administrator

Upgrade an Exchange 2000 Site Replication Service (SRS) server to Exchange Server 2003

  • Exchange Full Administrator role applied at the organization level

  • Local Machine Administrator

  • Exchange 5.5 service account password

Upgrade to Exchange 2003 on an Exchange 2000 server in a domain

  • Exchange Full Administrator role applied at the organization level

  • Local Machine Administrator

For more information about managing and delegating permissions and user and group authorities, see the Exchange Server 2003 Administration Guide.

Exchange Server 2003 Security Considerations

Before installing Exchange Server 2003 in your organization, it is important that you are familiar with your organization's security requirements. Familiarizing yourself with these requirements helps ensure that your Exchange Server 2003 deployment is as secure as possible. For more information about planning Exchange Server 2003 security, see the following guides:

Exchange Server Deployment Tools

The Exchange Server Deployment Tools are tools and documentation that help with the upgrade and migration of your Exchange 2000 Server and Exchange Server 5.5 organization. To ensure that all of the required tools and services are installed and running properly, you are required to run Exchange Server 2003 Setup through the Exchange Server Deployment Tools.

For detailed steps, see How to Start the Exchange Server Deployment Tools.

Note

You must download the latest version of the Exchange Server Deployment Tools before you run them. To receive the latest version of the tools, see the Downloads for Exchange 2003 Web site.

After you start the tools and specify that you want to follow the process for Coexistence with Mixed Mode Exchange 2000 Server and Exchange Server 5.5, you are provided with the following options:

  • Upgrade Active Directory Connector servers

    This option includes a checklist for upgrading your ADC servers. This checklist includes the following steps:

    • Run ForestPrep.

    • Run DomainPrep.

    • Run ADC Setup.

    • Run ADC Tools.

    • Update ADC version on all servers before you upgrade your Exchange 2000 servers.

  • Install or Upgrade the First Exchange Server

    This option includes a checklist for installing or upgrading to Exchange Server 2003. This checklist includes the following steps:

    • Verify that your organization meets the specified requirements.

    • Remove unsupported components.

    • Run the DCDiag tool.

    • Run the NetDiag tool.

    • Run Exchange Setup.

With the exception of running the DCDiag and NetDiag tools, each of these installation steps is detailed later in this topic (it is recommended that you run the DCDiag and NetDiag tools on every server on which you plan to install Exchange Server 2003). Moreover, the remaining sections in this topic provide information about the concepts and considerations involved in migrating from Exchange Server 5.5 to Exchange Server 2003.

System-Wide Requirements for Exchange 2003

Before you install Exchange Server 2003, ensure that your network and servers meet the following system-wide requirements:

  • You have Windows 2000 Server Service Pack 3 (SP3) or Windows Server 2003 Active Directory.

  • Each Exchange Server 2003 server has access to a Windows global catalog server that is no more than one Active Directory site away.

  • You have Domain Name System (DNS) and Windows Internet Name Service (WINS) configured correctly in your Windows site.

  • You backed up your Exchange Server 5.5 databases, and backed up your servers running Windows 2000 or Windows Server 2003.

For more information about Windows 2000 Server, Windows Server 2003, Active Directory, and DNS, see the following resources:

Running Exchange 2003 ForestPrep

Even if you previously ran Exchange 2000 ForestPrep, you must still run Exchange 2003 ForestPrep.

Exchange 2003 ForestPrep extends the Active Directory schema to include Exchange-specific classes and attributes. ForestPrep also creates the container object for the Exchange organization in Active Directory. The schema extensions supplied with Exchange Server 2003 are a superset of those supplied with Exchange 2000 Server.

In the domain where the schema master resides, run ForestPrep once in the Active Directory forest. (By default, the schema master runs on the first Windows domain controller installed in a forest.) Exchange Setup verifies that you are running ForestPrep in the correct domain. If you are not in the correct domain, Setup informs you which domain contains the schema master. For information about how to determine which of your domain controllers is the schema master, see Windows 2000 or Windows Server 2003 Help.

The account you use to run ForestPrep must be a member of the Enterprise Administrator and the Schema Administrator groups. While you are running ForestPrep, you designate an account or group that has Exchange Full Administrator permissions to the organization object. This account or group has the authority to install and manage Exchange 2003 throughout the forest. This account or group also has the authority to delegate additional Exchange Full Administrator permissions after the first server is installed.

Important

When you delegate Exchange roles to a security group, it is recommended that you use Global or Universal security groups and not Domain Local security groups. Although Domain Local security groups can work, they are limited in scope to their own domain. In many scenarios, Exchange Setup needs to authenticate to other domains during the installation. Exchange Setup may fail in this case because of a lack of permissions to your external domains. The account or group your select does not override your previous account or previous delegations, it adds to them.

Note

To decrease replication time, it is recommended that you run Exchange 2003 ForestPrep on a domain controller in your root domain.

You can run Exchange 2003 ForestPrep from either the Exchange Server Deployment Tools or from the Exchange Server 2003 CD. For information about how to run Exchange ForestPrep from the Exchange Server Deployment Tools, see "Exchange Server Deployment Tools" earlier in this topic.

For detailed steps about how to run ForestPrep for Exchange Server 2003, see How to Run Exchange Server 2003 ForestPrep.

Running Exchange Server 2003 DomainPrep

After you run ForestPrep and allow time for replication, you must run Exchange  2003 DomainPrep. DomainPrep creates the groups and permissions necessary for Exchange servers to read and modify user attributes. Even if you previously ran Exchange 2000 DomainPrep, you must run Exchange  2003 DomainPrep. The Exchange Server 2003 version of DomainPrep performs the following actions in the domain:

  • Creates Exchange Domain Servers and Exchange Enterprise Servers groups.

  • Nests the global Exchange Domain Servers into the Exchange Enterprise Servers local group.

  • Creates the Exchange System Objects container, which is used for mail-enabled public folders.

  • Sets permissions for the Exchange Enterprise Servers group at the root of the domain so that Recipient Update Service has the appropriate access to process recipient objects.

  • Modifies the AdminSdHolder template where Windows sets permissions for members of the local Domain Administrator group.

  • Adds the local Exchange Domain Servers group to the Pre-Windows 2000 Compatible Access group.

  • Performs Setup pre-installation checks.

The account you use to run DomainPrep must be a member of the Domain Administrators group in the local domain and a local machine administrator. You must run DomainPrep in the following domains:

  • The root domain.

  • All domains that will contain Exchange Server 2003 servers.

  • All domains that will contain Exchange Server 2003 mailbox-enabled objects (such as users and groups), even if no Exchange servers will be installed in these domains.

  • All domains that contain global catalog servers that Exchange directory access components may potentially use.

  • All domains that will contain Exchange Server 2003 users and groups that you will use to manage your Exchange Server 2003 organization.

Note

Running DomainPrep does not require any Exchange permissions. Only Domain Administrator permissions are required in the local domain.

You can run Exchange 2003 DomainPrep from either the Exchange Server Deployment Tools or from the Exchange Server 2003 CD. For information about how to run Exchange DomainPrep from the Exchange Server Deployment Tools, see "Exchange Server Deployment Tools" earlier in this topic.

For detailed steps about how to run DomainPrep for Exchange Server 2003, see How to Run Exchange Server 2003 DomainPrep.

Server-Specific Requirements for Exchange Server 2003

Before you upgrade to Exchange Server 2003 or install a new Exchange 2003 Server, make sure that your servers meet the requirements that are described in this section.

Hardware Requirements

The following are the recommended hardware requirements for Exchange Server 2003 servers:

  • Intel Pentium or compatible 133 megahertz (MHz) or faster processor

  • 256 megabytes (MB) of RAM recommended minimum, 128 MB supported minimum

  • 500 MB of available disk space on the drive on which you install Exchange

  • 200 MB of available disk space on the system drive

  • CD-ROM drive

  • SVGA or higher-resolution monitor

For more information about hardware requirements for front-end and back-end servers, see Exchange Server 2003 and Exchange 2000 Server Front-End and Back-End Server Topology Guide.

File Format Requirements

To install Exchange Server 2003, disk partitions must be formatted for NTFS file system and not for file allocation table (FAT). This requirement applies to the following partitions:

  • System partition

  • Partition that stores Exchange binaries

  • Partitions containing transaction log files

  • Partitions containing database files

  • Partitions containing other Exchange files

Operating System Requirements

Exchange Server 2003 is supported on the following operating systems:

  • Windows 2000 SP3 or later

Note

Windows 2000 SP3 or later is available for download at the following site: Windows 2000 Service Packs. Windows 2000 SP3 or later is also a prerequisite for running the Exchange Server 2003 Active Directory Connector.

  • Windows Server 2003

Exchange 2000 Server Requirements

Before you upgrade your Exchange 2000 Servers to Exchange Server 2003, your servers must be running Exchange 2000 SP3 or later.

Exchange 2000 SP3 is available for download at the following site: Service Pack 3 for Exchange 2000 Server and Exchange 2000 Server Enterprise Edition.

Windows 2000 Components

When you are upgrading to Exchange Server 2003, the current state of the Post Office Protocol version 3 (POP3), Internet Message Access Protocol version 4 (IMAP4), and Network News Transfer Protocol (NNTP) services is preserved. Furthermore, if you are upgrading to Exchange Server 2003 on a server running Windows 2000, Exchange Setup automatically installs and enables the Microsoft .NET Framework and ASP.NET components, which are prerequisites for Exchange Server 2003.

Important

Unless it is necessary that you run a particular service, you should disable it. For example, if you do not use POP3, IMAP4, or NNTP, you should disable these services on all of your Exchange Server 2003 servers.

For more information about installing these components, see Windows 2000 Help.

Upgrading Exchange 2000 Active Directory Connector

Before you can upgrade your server running Exchange 2000 Active Directory Connector (ADC) to Exchange Server 2003, you must first upgrade the Exchange 2000 Server version of ADC to Exchange Server 2003.

For detailed steps, see How to Upgrade the Exchange 2000 Active Directory Connector.

Upgrading Front-End and Back-End Servers

Exchange Server 2003 supports the deployment of Exchange in a manner that distributes server tasks among front-end and back-end servers. Specifically, a front-end server accepts requests from POP3, IMAP4, and RPC/HTTP clients, and proxies them to the appropriate back-end server for processing.

If your mixed-mode Exchange 2000 Server and Exchange Server 5.5 organization takes advantage of front-end and back-end architecture, you must upgrade your Exchange 2000 Server front-end servers before you upgrade your back-end servers to Exchange Server 2003.

For more information about front-end and back-end architecture, see Configuring Exchange 2003 for Client Access.

For information about front-end and back-end scenarios, configurations, and installation, see the following guides:

Pre-Upgrade Procedures for Exchange 2000

Before you begin upgrading your Exchange 2000 Server organization to Exchange Server 2003, it is important that you prepare your organization for the upgrade process. This section provides recommended and required pre-upgrade procedures.

Upgrading the Operating Systems

If you plan to upgrade your Exchange 2000 Servers that are running Windows 2000 SP3 (or later) to Windows Server 2003, you must first upgrade those servers to Exchange Server 2003. This upgrade sequence is required because Exchange 2000 Server is not supported on Windows Server 2003.

Removing Unsupported Components

The following components are not supported in Exchange Server 2003:

  • Microsoft Mobile Information Server

  • Instant Messaging service

  • Exchange 2000 Conferencing Server

  • Key Management Service

  • cc:Mail connector

  • MS Mail connector

To upgrade an Exchange 2000 Server to Exchange Server 2003 successfully, you must first use Exchange Setup to remove these components. For more information about removing these unsupported components, see Exchange 2000 Help and Mobile Information Server Help.

Note

If you want to retain these components, do not upgrade the Exchange 2000 Servers that are running them. Instead, install Exchange Server 2003 on other servers in your organization.

Upgrading International Versions of Exchange

When you upgrade from Exchange 2000 Server to Exchange Server 2003, you must upgrade to the same language version of Exchange Server 2003, with the exception of the Chinese Traditional, Chinese Simplified, or Korean languages. For example, you cannot use Exchange Setup to upgrade a German version of Exchange 2000 Server to a French version of Exchange Server 2003.

Important

You can use Exchange Setup to upgrade an English version of Exchange 2000 Server to the Chinese Simplified, Chinese Traditional, or Korean versions of Exchange Server 2003. The Novell GroupWise connector, however, is not supported on any of these language versions. Therefore, if this connector is installed on your English version of Exchange 2000 Server, you must remove it before you can upgrade to Exchange Server 2003.

Upgrading Your Exchange 2000 Servers to Exchange Server 2003

After performing the pre-upgrade procedures, you can run Exchange Server 2003 Setup to upgrade your Exchange 2000 Servers to Exchange Server 2003. You can run Exchange Server 2003 Setup from either the Exchange Server Deployment Tools or from the Exchange Server 2003 CD.

For information about how to run Exchange Setup from the Exchange Server Deployment Tools, see "Exchange Server Deployment Tools" earlier in this topic.

For information about how to run Exchange Setup from the Exchange CD, see "Running Exchange 2003 Setup" in Upgrading from Exchange 2000 Server to Exchange Server 2003.

Installing a New Exchange Server 2003 Server

This section provides you with the necessary requirements and procedures to install a new Exchange Server 2003 server.

Note

You can install a new Exchange Server 2003 server before upgrading your existing Exchange 2000 Servers. It is not necessary that you perform the upgrade first.

Installing and Enabling Windows 2000 or Windows Server 2003 Services

Exchange Server 2003 Setup requires that the following components and services be installed and enabled on the server:

  • .NET Framework

  • ASP.NET

  • Internet Information Services (IIS)

  • World Wide Web Publishing Service

  • Simple Mail Transfer Protocol (SMTP) service

  • Network News Transfer Protocol (NNTP) service

If you are installing Exchange Server 2003 on a server running Windows 2000, Exchange Setup installs and enables the .NET Framework and ASP.NET automatically. You must install the World Wide Web Publishing Service, the SMTP service, and the NNTP service manually before running Exchange Server 2003 Installation Wizard.

If you are installing Exchange Server 2003 in a native Windows Server 2003 forest or domain, none of these services is enabled by default. You must enable the services manually before running Exchange Server 2003 Installation Wizard.

Important

When you install Exchange on a new server, only the required services are enabled. For example, POP3, IMAP4, and NNTP services are disabled by default on all of your Exchange Server 2003 servers. You should enable only services that are essential for performing Exchange Server 2003 tasks.

For detailed steps about how to install the IIS prerequisites for Exchange Server 2003 on the Windows 2000 platform, see How to Install IIS Prerequisites for Exchange Server 2003 on Windows 2000.

For detailed steps about how to install the IIS prerequisites for Exchange Server 2003 on the Windows Server 2003 platform, see How to Install IIS Prerequisites for Exchange Server 2003 on Windows Server 2003.

Running Exchange Server 2003 Setup

To install your first Exchange Server 2003 server in the forest, you must use an account that has Exchange Full Administrator permissions at the organization level and is a local administrator on the computer. You can run Exchange Server 2003 Setup from either the Exchange Server Deployment Tools or from the Exchange Server 2003 CD.

For information about how to run Exchange Setup from the Exchange Server Deployment Tools, see "Exchange Server Deployment Tools" earlier in this topic.

For detailed steps about how to install Exchange Server, see How to Install Exchange Server 2003.

For important information about post-deployment steps, see Post-Installation Steps for Exchange Server 2003. That topic includes information about how to verify that your Exchange installation was successful. It also includes information about the latest Exchange Server 2003 service packs and security patches.

Moving Exchange Server 5.5 Mailbox and Public Folder Contents

After upgrading the Exchange 2000 Servers in your organization and installing a new Exchange Server 2003 server, your next task is to move your Exchange Server 5.5 mailbox and public folder contents to your new Exchange Server 2003 server.

This section provides information about using Exchange Task Wizard to move your mailbox contents and using Microsoft Exchange Public Folder Migration Tool (PFMigrate) to move your public folder contents.

Using Exchange Task Wizard to Move Mailboxes

Exchange Task Wizard provides an improved method for moving mailboxes. You can now select as many mailboxes as you want, and then using the task scheduler, schedule a move to occur at a specified time. You can also use the task scheduler to cancel any unfinished moves at a specified time. For example, you can schedule a large move to start at midnight on Friday and terminate automatically at 6:00 A.M. on Monday, thereby ensuring that your server's resources are not being used during regular business hours. Using the wizard's improved multithreaded capabilities, you can move as many as four mailboxes simultaneously.

For detailed steps about how to move mailboxes using the Exchange Task Wizard, see How to Use Exchange Task Wizard to Move Mailboxes.

Using Microsoft Exchange Public Folder Migration Tool

The Microsoft Exchange Public Folder Migration Tool (PFMigrate) is a new tool that enables you to migrate both system folders and public folders to the new server. You can use PFMigrate to create system folder and public folder replicas on the new server and, after the folders have replicated, remove replicas from the source server. Unlike Exchange Server 5.5, you do not need to set a home server for a public folder in Exchange Server 2003. Any replica acts as the primary replica of the data it contains, and any public folder server can be removed from the replica list.

To determine how many system folders or public folders need to be replicated, use PFMigrate to generate a report before you actually run the tool. To determine whether the folders replicated successfully, you can generate the same report after you run the tool.

The PFMigrate tool is run from the Exchange Server Deployment Tools. For information about how to start Exchange Server Deployment Tools, see "Exchange Server Deployment Tools" earlier in this topic.

For detailed steps, see How to Run the Public Folder Migration (PFMigrate) Tool.

Note

After you run PFMigrate, only the hierarchy of the system folders and public folders is migrated immediately. You must wait for replication for the contents of the system folders and public folders to be migrated. Depending on the size and number of system and public folders, as well as your network speed, replication could take a considerable amount of time.

Switching from Mixed Mode to Native Mode

Because Exchange 2000 Server and Exchange Server 2003 are structured to take advantage of Active Directory functionality, there are some limitations when Exchange Server 2003 coexists in the same organization with Exchange Server 5.5. When Exchange 2000 Server or Exchange Server 2003 servers coexist with Exchange Server 5.5, your organization must run in mixed mode.

Running in mixed mode limits the functionality of Exchange Server 2003. Therefore, after migrating from Exchange Server 5.5 to Exchange Server 2003, it is recommended that you switch from mixed mode to native mode. This section discusses the advantages of a native-mode Exchange organization and provides the steps that are necessary to switch from mixed mode to native mode.

You are ready to change your Exchange Server 2003 organization to native mode if:

  • Your organization will never require interoperability between your Exchange Server 2003 servers and Exchange Server 5.5 servers in the same organization.

  • Your Exchange Server 5.5 servers exist in an organization that is separate from your Exchange Server 2003 servers.

Note

After you switch your Exchange Server 2003 organization from mixed mode to native mode, you cannot switch the organization back to mixed mode. Make sure that your Exchange Server 2003 organization will not have to interoperate with Exchange Server 5.5 in the future before you switch from mixed mode to native mode.

First, however, you should determine in which mode your Exchange organization is currently running. For detailed steps, see How to Determine if You Are Running Exchange in Mixed or Native Mode.

Exchange Server 2003 Considerations for Mixed and Native Mode

As mentioned earlier, after you migrate from Exchange Server 5.5 to Exchange Server 2003, by default, your organization runs in mixed mode. Running Exchange Server 2003 in mixed mode has the following disadvantages:

  • Exchange Server 5.5 sites are mapped directly to administrative groups.

  • Administrative groups are mapped directly to Exchange Server 5.5 sites.

  • Routing group membership consists only of servers that are installed in the administrative groups.

  • You cannot move Exchange Server 2003 servers between routing groups.

  • Because many Exchange Server 2003 features are available only when you run your Exchange Server 2003 organization in native mode, it is recommended that you switch from mixed mode to native mode. Running Exchange Server 2003 in native mode has the following advantages:

  • You can create query-based distribution groups. A query-based distribution group provides the same functionality as a standard distribution group. However, instead of specifying static user memberships, with a query-based distribution group you can use an LDAP query to build membership in the distribution group dynamically. For more information about query-based distribution groups, see "Managing Recipients and Recipient Policies" in the Exchange Server 2003 Administration Guide.

  • Your routing bridgehead server pairs use 8BITMIME data transfers instead of converting down to 7-bit. This equates to a considerable bandwidth saving over routing group connectors.

  • The Exchange store in Exchange Server 2003 ignores and removes zombie access control entries (ACEs) from the previous Exchange Server 5.5 servers in your organization automatically. These zombie access control entries are security identifiers from previous Exchange Server 5.5 servers that have been removed from your organization.

  • Routing groups can consist of servers from multiple administrative groups.

  • You can move Exchange Server 2003 servers between routing groups.

  • You can move mailboxes between administrative groups.

  • Simple Mail Transfer Protocol (SMTP) is the default routing protocol.

Removing Exchange Server 5.5 Servers

Before you can switch from mixed mode to native mode, you must remove all Exchange Server 5.5 servers in your organization. This section guides you through the process of removing the Exchange Server 5.5 servers from your organization.

Removing an Exchange Server 5.5 Server

Before you remove an Exchange Server 5.5 server from your site, verify that there are no mail connectors on the server. If there are, open a connector on another server in the site, and then verify mail flow. Next, remove the connectors on the server to be deleted. Retest message flow. For more information about removing your Exchange Server 5.5 connectors, see the Exchange Server 5.5 Help.

For detailed steps about how to remove Exchange Server 5.5 servers, see How to Remove Exchange 5.5 Servers from Your Exchange 2003 Organization.

Note

Ensure that the account to which you are logged on has Exchange Full Administrator permissions, as well as Exchange Server 5.5 service account administrator permissions for the site.

Important

If this is the first server in the site to be removed, see Microsoft Knowledge Base article 152959, "XADM: How to Remove the First Exchange Server in a Site" (https://go.microsoft.com/fwlink/?linkid=3052&kbid=152959).

Removing the Last Exchange Server 5.5 Server

Before you can switch from mixed mode to native mode, you must remove all Exchange Server 5.5 servers in your organization. This section guides you through the process of removing the last Exchange Server 5.5 server from your organization.

For detailed steps, see How to Remove the Last Exchange 5.5 Server from Your Exchange 2003 Organization.

Removing Site Replication Service

Site Replication Service (SRS) is a component that exchanges configuration information between Active Directory and the directory in Exchange Server 5.5. In Exchange Server 5.5, SRS is necessary because Exchange Server 5.5 configuration information can only be exchanged between Exchange Server 5.5 servers and Exchange Server 5.5 directories—not with Active Directory. SRS mimics an Exchange Server 5.5 directory so that other Exchange Server 5.5 servers can replicate information to it. Using the configuration connection agreement created by Exchange Setup, Active Directory Connector replicates the configuration information in SRS into Active Directory.

SRS runs only in a mixed-mode Exchange administrative group. SRS also performs additional functions, such as detecting and reacting to directory replication topology changes. You cannot switch from mixed mode to native mode until you have removed all instances of SRS.

SRS is enabled automatically in two situations:

  • On the first Exchange 2000 Server or Exchange Server 2003 computer that you install in an Exchange site that is running only Exchange Server 5.5 servers.

  • When you in-place upgrade to Exchange 2000 Server from an Exchange Server 5.5 server that is the directory replication bridgehead server for a site.

For detailed steps about how to remove Site Replication Service, see How to Remove Exchange SRS. After you complete these steps, you can convert the Exchange organization to native mode.

Switching to Native Mode

For detailed steps about how to switch from mixed mode to native mode, see How to Convert from Mixed Mode to Native Mode in Exchange.

After you switch your Exchange Server 2003 organization from mixed mode to native mode, you cannot switch the organization back to mixed mode. Before you perform the following procedure, make sure that your Exchange Server 2003 organization will not have to interoperate with Exchange Server 5.5 in the future.

To take full advantage of Exchange native mode, you must restart the Microsoft Exchange Information Store service on all of the Exchange servers in your organization. You do not need to restart all of the Microsoft Exchange Information Store services simultaneously, but you must restart the service on each server for the server to take advantage of all Exchange native mode features. Restart the service on your servers after the change to native mode has been replicated to your local Windows domain controller.

For detailed steps about how to restart the Microsoft Exchange Information Store service, see How to Restart the Microsoft Exchange Information Store Service.

Note

In the <Organization Name> Properties dialog box, the Change Mode button is unavailable if any Exchange Server 5.5 servers are present or SRS exists in the organization.

Uninstalling Exchange Server 2003

After ensuring that your organization meets certain prerequisites, you can run Exchange Setup to uninstall Exchange Server 2003. For detailed steps, see How to Uninstall Exchange Server 2003.