Move all mailboxes to an Exchange 2007 server in the organization. For more information, see How to Move a Mailbox Within a Single Forest.

Move all content from the public folder database on the legacy server to a public folder database on an Exchange 2007 server in the organization. For detailed steps, see How to Move Public Folder Content from one Public Folder Database to Another Public Folder Database.

On an Exchange 2007 server, for each offline address book (OAB), move the generation process to an Exchange 2007 server. For detailed steps, see How to Move the Offline Address Book Generation Process to Another Server.

To remove the public folder mailbox and stores, on the Exchange 2003 or Exchange 2000 server, use Exchange System Manager to perform the following steps:

1. Expand the server, expand the storage group that contains the public folder store, right-click the public folder store, and then click Delete.
   
2. In the dialog box that notifies you that the public folder store is the default store for one or more mailbox stores or users, click OK to select a new public folder store. In the Select Public Store dialog box, select a public folder store on an Exchange 2007 server, and then click OK.
   

Note:

In Exchange 2003 Service Pack 2 (SP2), Exchange System Manager prevents you from removing a public folder store until all the public folder replicas have completed their background move process. Moving replicas can take several hours, or even days. If you remove a public folder store before replication has completed, you could lose public folder data. If you are running Exchange System Manager on an earlier version of Exchange, such as Exchange 2000, you must manually verify that the public folder replicas have moved before you remove the public folder store. To verify that the public folder replicas have moved, in Exchange System Manager, expand the server from which the replicas are moving, expand the storage group that contains the public folder store, expand the public folder store, and then select Public Folder Instances. If the details pane is empty for the public folder instances, the replicas have moved, and you can safely remove the public folder store.

Verify that Internet mail flow is configured to route through your Exchange 2007 transport servers. By default, Exchange 2007 does not enable Internet mail flow. Use one of the following methods to configure Internet mail flow:

• Deploy an Edge Transport server and subscribe it to the Exchange organization. This is the preferred method. This method automatically creates the required Send connectors for Internet mail flow. For more information, see How to Configure Internet Mail Flow Through a Subscribed Edge Transport Server.
  
• Deploy an Edge Transport server and manually configure the required Send and Receive connectors for Internet mail flow. For more information, see How to Configure Mail Flow Between an Edge Transport Server and Hub Transport Servers Without Using EdgeSync.
  
• You can send and receive Internet mail by relaying through Microsoft Exchange Hosted Services or other third-party SMTP gateway servers. For information, see How to Configure Internet Mail Flow Through Exchange Hosted Services or an External SMTP Gateway.
  
• You can configure the Hub Transport server to send and receive Internet mail directly. For more information, see How to Configure Internet Mail Flow Directly Through a Hub Transport Server.
  

Note:
Before you remove your last legacy server, verify that you have created Exchange 2007 Send connectors to replace all outbound SMTP connectors that may exist on that Exchange 2003 or Exchange 2000 server. Also, verify that the Exchange 2003 or Exchange 2000 server is not listed as the smart host for any Exchange 2007 Send connector or third-party SMTP gateway.

Important:
Verify that you have made any required changes to your Domain Name System (DNS) MX resource records so that SMTP traffic from the Internet is routed to the Internet-facing mail server you configured in this step. To determine which address the MX record resolves to, you can use the NSlookup command-line tool. For more information, see Nslookup.

To verify that all inbound protocol services (ActiveSync, Microsoft Office Outlook Web Access, Outlook Anywhere, POP3, IMAP4, Autodiscover service, and any other Exchange Web service) point to an Exchange 2007 Client Access server, perform the following steps:

1. Make sure that the Internet hostnames and IP addresses are appropriately configured in DNS for access to Exchange 2007 Client Access servers. For more information about publishing Exchange 2007 servers to allow clients to access their mailboxes from the Internet, see Publishing Exchange Server 2007 with ISA Server 2006.
   
2. Make sure that your clients are configured correctly.
   

Delete the routing group connectors that connect the Exchange 2003 or Exchange 2000 routing groups and the Exchange 2007 routing group. You can do this from Exchange 2003 or Exchange 2000 System Manager, or you can use the Remove-RoutingGroupConnector cmdlet in the Exchange Management Shell. For more information, see Remove-RoutingGroupConnector.

If you have Exchange 2003 or Exchange 2000 recipient policies that are only Mailbox Manager policies and do not define e-mail addresses (they do not have an E-mail Addresses (Policy) tab), perform the following steps to delete the policies:

1. In Exchange System Manager, expand Recipients, and then select Recipient Policies.
   
2. To verify that a policy is only a Mailbox Manager policy, right-click the policy, and then select Properties. The Properties page must not have an E-Mail Addresses (Policy) tab.
   
3. To delete the policy, right-click the policy, and then select Delete. Click OK and then click Yes.
   

If you have Exchange 2003 or Exchange 2000 policies that are both E-mail Addresses and Mailbox Manager policies (they have both the Mailbox Manager Settings (Policy) tab and the E-mail Addresses (Policy) tab), perform the following steps to remove the mailbox manager portion of the policy:

1. In Exchange System Manager, expand Recipients, and then select Recipient Policies.
   
2. Right-click the policy, and then select Change property pages.
   
3. Clear the Mailbox Manager Settings check box, and then click OK.
   

Note:
Do not delete any e-mail address recipient policies that have e-mail addresses that you still want defined in your organization. Exchange 2007 will use those policies when provisioning new recipients.

On your Exchange 2003 or Exchange 2000 server, perform the following steps to move the public folder hierarchy from the Exchange 2003 or Exchange 2000 administrative group to the Exchange 2007 administrative group:

1. In Exchange System Manager, expand Administrative Groups, right-click Exchange Administrative Group (FYDIBOHF23SPDLT), select New, and then select Public Folders Container.
   
2. Expand the Exchange 2003 or Exchange 2000 administrative group that contains the public folder tree, expand Folders, and then drag Public Folders to Folders under the Exchange 2007 administrative group.
   

Note:
If you do not complete this step, the Exchange 2007 public folder database could fail to mount if you delete the Exchange 2003 or Exchange 2000 administrative group.

Perform the following steps to delete the domain Recipient Update Services:

1. In Exchange 2003 or Exchange 2000 System Manager, expand Recipients, and then select Recipient Update Services.
   
2. Right-click each domain Recipient Update Service, and then select Delete.
   
3. Click Yes.
   

You will not be able to delete the Recipient Update Service (Enterprise Configuration) by using Exchange 2003 or Exchange 2000 System Manager. Perform the following steps to delete the Recipient Update Service (Enterprise Configuration) by using ADSI Edit (AdsiEdit.msc):

1. Open ADSI Edit, expand Configuration, expand CN=Configuration,CN=<domain>, expand CN=Services, expand CN=Microsoft Exchange, expand CN=<Exchange organization name>, expand CN=Address Lists Container, and then select CN=Recipient Update Services.
   
2. In the result pane, right-click Recipient Update Service (Enterprise Configuration), click Delete, and then click Yes to confirm the deletion.
   

Caution:
Do not use ADSI Edit to modify or delete any Exchange 2007 objects. This step is to remove only legacy objects that Exchange 2007 does not need.

Note:
AdsiEdit.msc is included on the Microsoft Windows Server 2003 CD in Support\Tools. For more information about ADSI Edit, see Adsiedit Overview.

Uninstall Exchange 2003 or Exchange 2000 by using Add or Remove Programs from Control Panel. For more information, see How to Uninstall Exchange Server 2003 or How to Uninstall Exchange 2000 Server.

Note:

If you want to use Exchange System Manager to manage public folders, details templates, or address templates through a graphical user interface, you can keep Exchange System Manager installed even though you remove the last Exchange 2003 or Exchange 2000 server. To keep Exchange System Manager, on the Component Selection page of the Microsoft Exchange Installation wizard, select Change for the Microsoft Exchange component, select Remove for the Microsoft Exchange Messaging and Collaboration Services component, and select None (Installed) for the Microsoft Exchange System Management Tools component.

Caution:

Before you remove any Exchange 2003 or Exchange 2000 administrative groups that contained mailboxes, verify that the public folder hierarchy has been moved to another administrative group. Also, verify that the Free/Busy public folder has replicated to the servers in other administrative groups. The general process to create public folder replicas on servers in other administrative groups is to update the replica list for each public folder to specify the destination server. After you allow sufficient time for the data to be replicated to the destination server, verify that the public folder database is empty. To do this, use the Exchange System Manager Public Folder Instances node or use the get-PublicFolderStatistics cmdlet. If the results are blank, the public folder database is empty. When you remove the public folder database, you may be prompted to select another public folder database to act as the site folder for administrative groups and offline address books (OABs). You may also be prompted to select another public folder database to act as the default public folder database for some messaging databases. For these prompts, the site folder server represents the public folder database that is responsible for making sure that administrative group and OAB site folders exist. The site folder server may be any public folder database server in the organization. The site folder server does not delete site folders for missing administrative groups. However, the site folder server does remove site folders for missing OABs.

Microsoft strongly recommends against removing the original Administrative groups from an organization. If any of the original Exchange 2003 or Exchange 2000 administrative groups have been removed, verify that mail continues to flow and does not build up in the System Attendant mailboxes on Exchange 2007 servers. Also, verify that public folder Free/Busy information is updated successfully for Outlook 2003 and earlier clients. If mail builds up in the System Attendant mailboxes, or if Free/Busy information is not updated successfully, the LegacyExchangeDN attribute of the affected user(s) may point to a deleted Administrative group. In this situation, you must change the LegacyExchangeDN attribute for the affected users. To do this, follow these steps:

1. Download the Admodify.exe tool from http://www.codeplex.com/admodify, and then extract the contents of the .zip file to a folder.
   
2. Double-click Admodify.exe, and then click Run if you are prompted to run the program.
   
3. In the ADModify.NET dialog box, click Modify Attributes.
   
4. Under Domain List, click the domain entry that corresponds to the domain in which the affected Exchange server is located. For example, click DC=corp,DC=example,DC=com. 
   
5. Under Domain Controller List, click the fully qualified domain name of the domain controller that hosts the affected Exchange users. For example, click DC-1.corp.example.com. 
   
6. Click to clear the following check boxes:
   Groups
   Contacts
   Public Folders
   Show Containers Only
   

   Note:
   Do not clear the Users check box.

7. Click the green arrow button that is beside Domain Controller List.
   
8. Under Domain Tree List, expand the domain object that is displayed.
   
9. Click the container in which the affected users are located. For example, click Users.
   
10. Click Add to List, click Select All, and then click Next.
    
11. Click the Custom tab, and then click to select the Make a customized attribute modification check box.
    
12. In the Attribute Name box, type LegacyExchangeDN.
    
13. In the Attribute Value box, type an entry that corresponds to the string value that is appropriate for your organization. You must replace the last part of the string value with a variable that is appropriate for all the users. For example, type a value that resembles the following:
    /o=First Organization/ou=Exchange Administrative Group (Internal_Name)/cn=Recipients/cn=%'Alias'
    In this example, the following information applies to the cn=%'Alias' part of the string value:
    - The percent sign (%) is included to indicate the division between a literal value and a variable.
    - A single quotation mark (') is used before and after the variable.
    - Alias is the variable that applies to all the users.
    
14. Click Go.
    

After the last Exchange 2003 or Exchange 2000 server has been removed from the Exchange 2007 organization, the Write DACL inherit (group) right for the Exchange Servers group should be removed from the root of the domain by running the following command:

Remove-ADPermission "dc=<Domain>" -user "<RootDomain>\Exchange Enterprise Servers" -AccessRights WriteDACL -InheritedObjectType Group

After the last Exchange 2003 or Exchange 2000 server has been removed from the Exchange 2007 organization, you can also remove the legacy Exchange Domain Servers and Exchange Enterprise Servers security groups.

Caution:

Before deleting either of these security groups, you should verify that each group is empty and it is not being used for any other purpose or process. If one or both of these groups has members, but all members are shown as security identifiers (SIDs), then the groups can be safely removed. If one or both groups has members, and the members are resolved to computer names, you should verify that the computers are not functioning Exchange servers before you delete the groups.