The licensing model of CodeTwo Exchange Migration is based on the total number of source mailboxes that will be migrated. Each migrated mailbox consumes one license.

Regardless of the number of licenses that you purchase, you will only receive one license key. The key contains information on how many mailboxes can be migrated with the software. You can run several migration jobs on multiple machines using the same license key until you run out of individual licenses.

A single license is consumed for each source mailbox matched in the Match mailboxes step when you start a migration job. Once the license has been consumed (assigned to a mailbox), reassigning it to another source mailbox is no longer possible.  Mailboxes are counted by the licensing system only once, based on:

  • their GUID, when migrating via the EWS or MAPI protocol;
  • the number of source email addresses specified in the CSV file used for migration, when migrating via the IMAP protocol.

Mailbox GUID is also the only piece of information about your users that is stored in our licensing system. We do not store SMTP email addresses, or any other Active Directory data associated with a mailbox.

Source mailboxes that have already been counted by the licensing system can be migrated as many times as you want. The same source mailbox will not consume more than one license, even if you restart the migration job, use the Run delta migration button, configure a new job with the same mailboxes, etc. The only exception is when you migrate source mailboxes via IMAP and later attempt to migrate the same mailboxes using the EWS or MAPI protocol. Learn more

Note that when matching mailboxes, the software lists all source mailboxes in the alphabetical order. If you decide to buy a license key for fewer mailboxes than the number of mailboxes existing in your organization, you will have to manually choose mailboxes that you want to migrate. If you need to migrate more mailboxes, you can buy additional licenses at any time.


You bought a license key that allows you to migrate 50 source mailboxes. You have already migrated 25 mailboxes to another server. As a result, you still have 25 licenses left. You can use them to migrate mailboxes from any other Exchange server, Office 365 tenant or IMAP source – migration via IMAP takes the same number of licenses as the migration of Exchange mailboxes.

Accessing licensing details

To see detailed information on your license, including the number of mailboxes that you can migrate, go to Dashboard and in the Help card click the Licensing link. This will open the Licensing window (Fig. 1.).

Migratory - licensing - full
Fig. 1. Licensing details.


The program's licensing service requires an internet connection to retrieve information regarding your license.

The Licensing window displays:

  • your license key;
  • the type of your license (full or trial);
  • the date when your license will expire / has expired. In the case of CodeTwo Exchange Migration, the full license is unlimited in time;
  • the Buy/Expand button that links to the order page, from where you can purchase the license key or buy additional licenses;
  • the number of available and already consumed licenses.

The Licensing window also contains the Activate button. Read this article to find out more about activating the program.

Archive mailboxes licensing

When migrating mailboxes from Exchange server or Office 365, a single license allows you to migrate both the primary and archive mailboxes (In-Place Archives) of a single user. This means you don't need to buy additional licenses to migrate archive mailboxes.


You bought a license key that allows you to migrate 50 source mailboxes. If these mailboxes also have archive mailboxes enabled, you can migrate up to:

  • 50 primary mailboxes and 50 archive mailboxes, or
  • 50 primary mailboxes only, or
  • 50 archive mailboxes only.

Public folders licensing

Note that the migration of public folders takes 100 licenses out of the license pool. This number is fixed and doesn't depend on the actual size or number of migrated public folders. 


You bought a license key for 200 source mailboxes and then migrated the source public folders to the target server. You will still be able to migrate either 100 mailboxes (from the same source server or a different one) or public folders from another Exchange server or Office 365 tenant.

Using the same license key on multiple machines

Once a license is consumed to migrate a specific source mailbox, attempting to migrate the same mailbox by using another instance of the program (installed on a different PC) will not consume another license. Keep in mind, however, that only the information about the license being used is shared between these machines, not the information about the migrated data itself.


For that reason, we don't recommend migrating data between the same source and target servers on two or more different machines, as it could end up creating duplicated items on the target mailboxes.

Migrating Exchange mailboxes via IMAP

When migrating data using the IMAP protocol, licenses are consumed for every source mailbox specified in the CSV file. To protect the privacy of your data, the email addresses of these mailboxes are not stored by our licensing system. That is why if you try to migrate the same mailboxes later via the EWS or MAPI protocol, both of which use the mailbox GUID for licensing purposes, the program will not recognize that these mailboxes have already been licensed. As a consequence, the program will either assign them new licenses or display a warning about an insufficient number of licenses required to perform the migration job.

It is recommended to use the EWS protocol (for Exchange 2010 with SP 1 and later) or the MAPI protocol (for Exchange 2010 without SP1 and earlier) to migrate source on-premises Exchange mailboxes.

See also

Trial version – this article contains information on the trial version.
Activation – this article describes the activation procedure of the program.
License Agreement – this article contains the terms and conditions of using the CodeTwo software.

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