Inter-Organizational Migration to Exchange Server 2003 Using Exchange Server Migration Wizard - Part 1


Última modificación del tema: 2006-10-30

By Nino Bilic.

This article covers a subject that many customers may be facing: upgrading from Microsoft® Exchange Server 5.5 to Exchange Server 2003 and migrating data. This article is part 1 of two articles.

When you run the Microsoft Exchange Installation Wizard, if you choose to create a new Exchange Server 2003 organization instead of joining your existing Exchange Server 5.5 organization, you must use the Exchange Server Migration Wizard to move your mailboxes from Exchange Server 5.5 to Exchange Server 2003. This section provides instructions for migrating your Exchange directory and mailbox data to Exchange Server 2003.

Migration is the process of moving your existing Exchange Server 5.5 messaging system to Exchange Server 2003. This process involves using the Migration Wizard to export a copy of your existing mailboxes, messages, and other data, and then import that information into Exchange Server 2003.


Item Notes

Directory information

Migration Wizard migrates a subset of the attributes from the Exchange 5.5 directory to the Active Directory® directory service user object that was created for the migrated mailbox.

Mailbox content

Migration Wizard migrates the messages and information in the Calendar, Contacts, Deleted Items, Drafts, Inbox, Journal, Notes, Sent Items, and Tasks folders. The folder structure of the Exchange Server 5.5 mailbox is mirrored in the Exchange Server 2003 mailbox.


Item Notes

Inbox rules

Inbox rules must be re-created after migration.

Public folders

Migration Wizard does not migrate either public folder content or the public folder hierarchy. This includes messages and other items, such as forms, stored in public folders.

Public folder permissions

Migration Wizard does not maintain public folder properties or permissions for migrated mailboxes. After migration, migrated mailboxes must have their public folder permissions updated in the destination site by the administrator.

Out-of-office messages

If a user selects the I am currently Out of the Office option (using the Out of Office Assistant) and migration occurs while this option is selected, the option will be reset. After migration, the I am currently Out of the Office option must be reset.

Offline folder files

Migration Wizard does not update the offline folder files for each migrated mailbox. Because the offline folder files might be outdated, mailbox users who have offline folders must delete them after migration.

Offline address books

Migration Wizard does not maintain offline address books during migration. Default settings are added to any customized settings. After migration, you must regenerate offline address books and users must download them after regeneration.


Migration Wizard does not update the profile of each migrated mailbox. Mailbox users must create new profiles.

Personal Address Book

Migration Wizard does not update entries in the Personal Address Book stored on a client computer. When you migrate an Exchange 5.5 mailbox, Personal Address Book entries for the mailbox user no longer contain valid addresses.

Signature validation

Migration Wizard does not maintain signature validation. Users with advanced security might not be able to validate the signatures on messages that were sent before migration.

Encrypted messages

Existing encryption keys will not be available after migration. To avoid the risk of losing access to messages if their keys are lost, users should decrypt encrypted messages before migration.

Migration Wizard migrates a subset of attributes from the Exchange Server 5.5 directory to the Active Directory user object for the migrated mailbox.


Exchange Server 5.5 attributes Attribute names in Active Directory


displayName (also used as cn value)









Extension-Attribute-1-15 (also known as CustomAttribute 1 – 15)

ExtensionAttribute1 - 15









































To check the common names of Exchange Server 5.5 attributes, use the Exchange Server 5.5 Administrator tool in raw mode.

When Migration Wizard migrates Exchange Server mailboxes, it copies directory and mailbox information from the source Exchange Server 5.5 server and directory service to the target Exchange Server 2003 server and Active Directory forest. The steps Migration Wizard performs to accomplish these tasks are based on searches for user objects and contacts in Active Directory.

Migration Wizard searches the target Active Directory for user objects that match the mailboxes selected for migration. For each security identifier (SID) not found in Active Directory, Migration Wizard creates a disabled user object that corresponds to the account that you are migrating. Most matches are based on Microsoft Windows-based SIDs. In addition, Exchange Server 5.5 uses the SID to associate mailboxes with Windows user accounts.

If Migration Wizard finds a user object in Active Directory that matches the mailbox to be migrated, Migration Wizard:

  • Connects to the source directory.
  • Copies attributes from the source user object.
  • Merges directory information from the source user object with the user object in the target Active Directory forest.
  • Creates a mailbox on the target Exchange Server 2003 server.
  • Connects to the source Exchange Server 5.5 server.
  • Copies mailbox content from the source mailbox to the new mailbox on the target Exchange Server 2003 server.

If you migrate mailboxes to a new Active Directory forest but you keep the user objects in the current domain or forest, Migration Wizard will not find the appropriate SIDs in the target Active Directory. In this case, Migration Wizard:

  • Creates a mailbox on the target Exchange Server 2003 server.
  • Connects to the source Exchange Server 2003 server.
  • Copies mailbox content from the existing mailbox to the new mailbox on the target Exchange Server 2003 server.
  • Gives the source user object rights to access the target Exchange Server 2003 mailbox.
    A trust relationship must exist between the source and target domains to allow the source user object to access its new Exchange Server 2003 mailbox. For more information about creating a trust relationship between separate domains, see the Windows 2000 Server or Windows Server 2003 Help.
    The Windows Account Creation and Association page in Migration Wizard lists the mail accounts that you selected for migration. If an existing user object is located in Active Directory, the existing user object's distinguished name is shown in the Existing Windows Account column. If a disabled user object is created for the mailbox account, the disabled user object's distinguished name is shown in the New Windows Account column.

After searching for user objects, Migration Wizard searches Active Directory for contacts that match the mailboxes that are selected for migration. When a match is found, Migration Wizard:

  • Reads directory information from the contact.
  • Merges the information from the contact's attributes with the attributes for the new user object.
  • Deletes the contact object.

The directory information from the contact object is merged with the user object's attributes based on the following rules:

  • The target Active Directory is the most recent directory service.
  • An attribute will not be overwritten if the target value already exists.
  • Source multivalued attributes are preserved.
  • An attribute will not migrate if it is not part of the target schema.

If Migration Wizard does not find any contacts, it considers the search process to be complete (no new objects are created).

Before you migrate mailboxes from Exchange Server 5.5 to Exchange Server  2003, you must perform initial migration tasks. Additionally, the mailbox owners must complete specific initial migration tasks. To prepare to migrate from Exchange Server  5.5, you need to:

  • Reduce the amount of Exchange Server  5.5 data to be migrated as much as possible.
  • Use Active Directory Connector to establish coexistence (if necessary) between Exchange Server  5.5 and Exchange Server  2003 while you are migrating Exchange Server  5.5 data. If you require full replication between the Exchange Server  5.5 directory and Active Directory, establish an inter-organizational connection agreement.
  • Identify resource mailboxes.
  • Ensure that the owners of the Exchange Server  5.5 mailboxes that will be migrated perform the initial user tasks.
    When you upgrade an Exchange Server  5.5 server with an Internet Mail Connector that is configured to forward mail through a smart host, you should be aware if the smart host resides in an Exchange 2000 Server administrative group that consists of multiple routing groups. In such a scenario, Active Directory Connector designates the first routing group that it finds as the connected routing group for the upgraded SMTP connector (displayed on the connector's Connected Routing Groups tab). Even if the smart host is identified correctly by the SMTP connector, unless the correct routing group is chosen, all messages routed through the SMTP connector will result in non-delivery reports (NDRs) for those messages. To prevent NDRs, after migration, configure the SMTP connector manually with the correct connected routing group.

Before you run Migration Wizard, it is recommended that you reduce the amount of Exchange Server 5.5 directory information and mail data as much as possible to ease the migration process. You can reduce the amount of data both before migration begins and during the migration process. Two ways to reduce data before you begin the migration are:

  • Delete outdated files from your Exchange mail system.
  • Instruct users to delete old mail and calendar data.

During the migration process, you can use Migration Wizard to reduce the amount of data that you migrate. On the Account Migration page, ensure that only the user accounts that you want to migrate are selected. On the Migration Information page, use the following options to specify what data should or should not be migrated:

  • To migrate messages that are dated within a specific time period, select Migrate Mail messages within a date range. Then specify a date range by typing a starting date in the Date Range box and an ending date in the To box.
  • To avoid migrating mail messages with specific subjects, such as a list of words or letters, select Do not migrate mail messages with specific subjects. In Subject List File, click Browse to locate the file that contains the subjects that you want to filter.
    The files in Subject List File must be saved in Unicode file format.

To install the Exchange Server 2003 version of Active Directory Connector (ADC), you must have at least one server in each Exchange site running Exchange Server 5.5 SP3. The account that you use to install ADC must be a member of the Enterprise Administrator, Schema Administrator, and Domain Administrator groups. The account must also be a Local Machine Administrator on the local machine.

You can migrate Exchange Server 5.5 mailboxes without using Active Directory Connector and connection agreements. Active Directory Connector is required only when:

  • Your organization requires coexistence during the migration period.
  • You want mailbox directory replication between the Exchange Server 5.5 directory and Active Directory.

Coexistence during migration is the recommended solution when you want to ensure that users in Exchange Server 5.5 and Exchange Server 2003 organizations can exchange mail during the migration process. When you connect Exchange Server 5.5 and Exchange Server 2003, the two systems coexist. Message transfer and directory synchronization must occur during the coexistence period. You can use an SMTP connector for message transfer. For directory synchronization, you can use Active Directory Connector.

If you use ADC while you migrate your Exchange Server 5.5 mailboxes, adhere to the following guidelines:

  • Use inter-organizational connection agreements.
  • Establish replication between Exchange Server 5.5 and Exchange Server 2003 by configuring two one-way inter-organizational connection agreements between the Exchange Server 5.5 server and Active Directory.
  • Configure the inter-organizational connection agreements to create contacts in Active Directory. To do this, on the Advanced tab of the connection agreement Properties dialog box, select Create a Windows contact. Contacts are created only when Active Directory Connector is replicating a mailbox whose primary Windows NT account does not exist in Active Directory.
  • Configure the inter-organizational connection agreement whose target container is in Active Directory to include X500 addresses with replicated objects. By default, Active Directory Connector does not include X500 addresses with user objects. Use either the Active Directory Administration Tool (Ldp.exe) or the ADSI Edit snap-in to assign the values SMTP,X500 to the msExchInterOrgAddressType attribute on the connection agreement object in Active Directory.
    Ldp.exe and ADSI Edit are available on the Windows 2000/2003 Server compact disc in the \Support\Tools folder. For more information about how to use Ldp.exe and ADSI Edit, see the Windows 2000 Server Help.
  • Suspend replication before you run Migration Wizard.
  • Restore replication after Migration Wizard finishes and the migrated mailboxes have been removed from Exchange Server 5.5.

Although inter-organizational connection agreements can only be configured to replicate in one direction, you can achieve coexistence by configuring two one-way inter-organizational connection agreements between the Exchange Server 5.5 server and Active Directory. Setting up two one-way ADC inter-organizational connection agreements that point in opposite directions enables the inter-organizational ADC to replicate the Exchange Server 5.5 directory information to Active Directory and to stamp replicated objects with the X500 address of the Exchange Server 5.5 mailbox. If you use the inter-organizational Active Directory Connector for directory synchronization during coexistence, do so only during the migration process.

When you establish two one-way inter-organizational connection agreements, ensure that the target container of one connection agreement is not the source container of the second connection agreement.

The Exchange Server 5.5 migration process uses X500 addresses in two different ways:

  • To ensure reply functionality for e-mails that are sent to a mailbox owner after migration.
  • As a search criterion when looking for Active Directory user objects that have already been created for mailboxes selected for migration.

Ensure that the connection agreement includes X500 addresses with replicated objects.

A primary mailbox is the mailbox where a user receives mail. A non-primary (or resource) mailbox is a mailbox created for resources such as conference rooms or group mailboxes. Resource mailboxes are owned by users who also own a primary mailbox. In Exchange Server 2003, a mailbox is an attribute of an object in Active Directory, not an object itself. Therefore, each user object in Active Directory can only be matched to one mailbox, which is the user's primary mailbox.

Resource mailboxes become separate objects in Active Directory during the migration process. For this reason, resource mailboxes must be identified before running Migration Wizard so that Migration Wizard handles them differently than primary mailboxes. Migration Wizard identifies resource mailboxes that are to be migrated by searching for the value NTDSNoMatch in the custom attributes for each resource mailbox. For this reason, if a user has a primary mailbox and one or more resource mailboxes, all mailboxes but the primary mailbox must be stamped with the value NTDSNoMatch.

Migration Wizard will only migrate multiple mailboxes that are associated with the same user if all but one of the mailboxes are stamped with the value NTDSNoMatch.

In addition to the initial migration tasks that you must perform, mailbox users must perform the following tasks before you run Migration Wizard:

  • Remote access users must synchronize their offline folder store (.ost) files with the Exchange Server 5.5 server so that any messages in their Outbox will be sent.
  • Exchange client and Schedule+ users must synchronize their schedule (.scd) file with the Exchange Server 5.5 server.
  • Users must decrypt encrypted messages.