Cross-forest migration from Exchange 2007 to Exchange 2010/2013/2016

I. Pre-migration activities

Before you install and configure CodeTwo Exchange Migration make sure that your environment (both the source and target server) is prepared for migration.

Below you will find the list of key points to be considered:

Step 1: Prepare a clean target Exchange environment in a new Active Directory forest

The following points need to be revised:

Step 2: (Optional) Enable the two-way trust relationship between the forests

Learn more about creating a forest trust on Windows Server 2008

This step is not necessary but recommended. Trust setup process will most likely reveal any issues you would otherwise find only during the actual migration and of course, it is better to address those before starting the migration.

* Please note that setting the trust relationship doesn't apply to SBS based environments.

Step 3: Configure mail flow between the source and the target server

Step 4: Prepare domain accounts on the target server

  • Migrate domain accounts between the Active Directory forests. You may do it automatically using Active Directory Migration Tool (ADMT) or create the accounts manually in the target forest.
  • During the mailboxes matching step, you can also set the program to create the mailboxes and the corresponding users automatically.

    Important

    Please be aware that prior to migration you have to prepare (in the target environment) a mailbox-enabled user account for each user included in the migration.

    What is more, if you choose either to manually create the mailboxes or allow the program to prepare them for you, be advised that the account data (such as permissions) will not be migrated.

Step 5: Make sure that the account used to connect to the source server belongs to the appropriate AD group and has its mailbox configured correctly

  • Check if the selected account belongs to the Exchange Organization Administrators group.
  • Ensure that this account has a valid, non-hidden mailbox on the source Exchange server.

Step 6: Verify the configuration and rights of the admin account that will be used to connect to the target Exchange server

Make sure that the target admin account is assigned the necessary management roles and that this account is mailbox-enabled.

Verify the following:

  1. Check if the target admin account has the following roles assigned:
    • ApplicationImpersonation
    • View-Only Recipients
    • View-Only Configuration
    • Public Folders*
    • Mail Recipient Creation*
    • Mail Recipients*

      Important

      Please note that the Public Folders role is only required if you plan to migrate public folders. Moreover, the Mail Recipient Creation and Mail Recipients roles are required to create new users and mailboxes. Therefore, it's not required to assign them to the admin account if you are migrating data to the mailboxes that already exist on the target server.

      The program will check if these roles are assigned to the admin account during the Configuration step of the Target server connection wizard. However, before you even start the program, you can manually:
      • check which roles are assigned to a specific user. To do that, run the Exchange Management Shell on the target server and enter the following cmdlet: Get-ManagementRoleAssignment -RoleAssignee “UserName”, where instead of UserName you need to enter a valid Name or Alias of your mailbox-enabled AD user; or
      • check which users are assigned a specific role. To do that, run the Exchange Management Shell on the target server and enter the following cmdlet: Get-ManagementRoleAssignment –Role “RoleName”, where instead of RoleName you need to enter a specific role, e.g. ApplicationImpersonation.
      If any required roles are missing, you can either assign them manually, following the steps described in this KB article, or let the program assign them for you in the Configuration step of the connection wizard.
  2. Access to the target server's EWS service using IP or Domain Name, e.g. https://[Exchange_IP]/EWS/Exchange.asmx or https://[Exchange_Name]/EWS/Exchange.asmx
  3. If a client connects to EWS from the outside of the local network he needs to have the external EWS URL correctly configured:
    • Open the Exchange Management Shell on the target server and check if the ExternalUrl is defined: Get-WebServicesVirtualDirectory | fl
    • If there's no address in the ExternalUrl line it needs to be defined. Execute the following script: Get-WebServicesVirtualDirectory | Set-WebServicesVirtualDirectory -ExternalUrl https://[Target server's internet name]/EWS/Exchange.asmx

Step 7: Adjust the EWS throttling settings and change the maximum size limit of sent mail to decrease the time of migration processing

Step 8: Installation of components required to install CodeTwo Exchange Migration on the source server (the installation wizard will guide you through this process)

  • MAPI CDO (MAPI Client and Collaboration Data Objects, required on any system except systems with coexisting MS Outlook x86 older than version 2016)
  • .NET 4.0 (required on any system, might be already installed)
    Learn more
  • PowerShell 2.0 (or higher, must be installed on Windows Server 2008)
    • Download Windows Management Framework Core (WinRM 2.0 and Windows PowerShell 2.0) for Windows Server 2008
    • Newer Windows releases (Windows 7 or higher, Windows Server 2008 R2 or higher) already have PowerShell 2.0 (or higher) built-in.
    • Small Business Server 2008 (SBS2008) users might stumble upon a problem with installing PowerShell. See our Knowledge Base article on that.

Step 9: Installation and activation of CodeTwo Exchange Migration

The program needs to be installed and activated on a machine within the source server domain.

Info

Please note that it is recommended to install the migration tool directly on the source server.

Info

Make sure you meet the system requirements prior to installing the software.

II. Migration process

The steps below will guide through the correct configuration of CodeTwo Exchange Migration:

Step 1: Connect to the source server

Important

Make sure that the software user who runs the migration is a local administrator.

When you start the program, you will see the Dashboard tab. Click Create a new migration job link on the How to start card. Select the source server type: Exchange Server. The Create Exchange migration job wizard will open. Set the name of the job and click Next to proceed to the Source mailboxes step. If this is your first migration job, you will need to configure connection to the on-premises Exchange Server that will be used as the source of your migration. Click Add new source connection in the Source server drop-down menu and a wizard will open. You need to complete the steps below:

  • Protocol – you need to select MAPI protocol if you connect to Exchange 2007.
  • Server connection – there you can allow the program to automatically recognize the Exchange server located within your network or select it manually from the picker.
  • Service account – in this step, the program creates a service responsible for accessing mailboxes selected for migration. As the service works under the administrator's MAPI profile, enter the administrator's email address and password. By default, the currently logged administrator's email address is filled in automatically. However, you can change it by clicking Browse and selecting another user's email address from the picker.
  • Configuration – this process configures your source server connection based on the entered settings.

If all data has been correctly entered, your source server mailboxes will be visible in the program.

If any errors appear, see Troubleshooting

Step 2: Select mailboxes you want to migrate and define target connection

After successfully configuring the source connection, you will get back to the migration job wizard.

The Source mailboxes step now allows you to include or exclude mailboxes by using multiple filters. You may, for example, include all users' mailboxes from a particular Organizational Unit or Active Directory group. By default, the program includes all users along with the Public Folders, because it is a most common scenario. Choose the mailboxes you want to migrate and proceed to the next step (Target mailboxes).

Now, set up a new target server connection by choosing Add new target connection from the Target server drop-down menu. A simple wizard will open.

  • In the Server connection step, choose either Autodiscover Exchange Server (default option) to automatically find the proper target server or configure the connection manually.

    Warning

    If you decided to configure the target connection manually, be aware that using an IP address will make granting impersonation rights and creating mailboxes impossible, unless you configure PowerShell Virtual Directory in IIS to allow basic authentication.

  • Admin account – provide a valid UPN and password of the account that will access the target server (remember that the admin account must fulfill the requirements specified in I Pre-migration activities, Step 6). Click Next to move on to the Configuration step.

    Info

    UPN (User Principal Name) is the name of a system user in an email address format. Learn more.

  • Configuration – this process configures the target Exchange server connection and checks whether the account provided in the previous step has the necessary roles assigned. If not, the program will attempt to assign them automatically. In such a case, you may be asked to provide the credentials of another account that belongs to the Organization Management role group. This account will not be used to connect to the target server, but only to assign the missing roles.

Once the configuration ends successfully, you will see green check marks. If any errors appear, see Troubleshooting.

After your connection is established, click Finish and proceed to the next step (Match mailboxes).

Step 3: Match target and source mailboxes

Matching the source with the target mailbox can be done in two ways: automatically via the built-in Automatch feature or manually. Either way, click the Match mailboxes button.

To match manually a single mailbox, click on Click to match target link in the Target user mailbox column and choose most appropriate option for this user. After selecting an option you may be asked to provide further details (e.g. password for newly created users). The available approaches are:

  • Create a new user - to create both Active Directory user and corresponding mailbox, using the defaults values that you can also change.
  • Choose an existing user from the list - to select an existing user in the target environment that does not have mailbox created yet
  • Manually specify the mailbox address - this option should be used in the case you are unable to list the target environment

However, when it comes to matching hundreds of mailboxes, the process may be extremely time-consuming. To automatically set the best available actions for desired users, simply select them on the list (you can use Ctrl+A shortcut to choose all entries) and eventually click Automatch. Select desired options and start the process.

When you have matched all your mailboxes you can continue to configure additional options.

Step 4: Customize all necessary aspects of the migration job

You may configure the following additional options:

  • Scheduler - allows you to set the job to be automatically started in desired period of times, so you do not have to control it manually.
  • Time filter - is used to exclude items that are older or newer than a particular date
  • Folder filter - may completely exclude specific folders from the migration process
  • Advanced settings - provides an option to define how many mailboxes should be migrated at same time. This number should correspond to the number of logical processors. You can also define the maximum size of items to be migrated.

Step 5: Start the migration

Move on to the JOBS tab and click Start on the toolbar to begin the migration.

Info

The migration processing time depends on several different factors, e.g. the number of mailboxes and items, the speed of internet connection, EWS throttling settings. We have published more details here.

Step 6: Check if the number of migrated items in the target mailboxes matches the source server mailboxes

If you notice any missing items in the target mailbox restart the migration using the Rescan feature.

Important

Please be aware that the program does not migrate some specific folders at all. Those are i.e. Sync Issues or ones created while putting a mailbox on a litigation hold.

Info

If any problems appear during the migration process they will be indicated on the dashboard, pointed on the reports and logged in the log files. Check out the software's diagnostics.

Step 7: Check if there are any new items in the source mailbox after migration

Once the migration is finished and you have noticed that some new items appeared in the migrated source mailbox, just restart the migration using the Rescan feature. Please keep in mind that the Rescan feature uploads only new items, not the changed ones.

III. Post-migration cleanup

Once the migration is completed please follow the points below:

Step 1: MX records

Change MX records with your domain registrar to enable mail flow to new servers instead of the old ones. Please note that this process may take several hours.

Warning

If any new items appear in a source mailbox while the MX records are being changed, it is possible to migrate them after the records' migration process is completed. It can be done by using the Rescan feature.

Step 2: The previous domain

Disconnect the previous domain and Exchange servers.

Info

If you have any problems with disconnecting your domain please consult your Domain Provider.

IV. Troubleshooting

For troubleshooting information, refer to our Knowledge Base.

For additional resources, refer to Frequently Asked Questions or contact us.

Was this information useful?