This is the fourth in a series of blogs taking you through the process of migrating from Exchange Server 2013 to 2016. In the part three, we covered installing Exchange Server 2016, configuring certificates, setting virtual directory URLs, and migrating the CAS role.

To read other parts in this series, go to:

Exchange 2013 to Exchange 2016 Migration (Part 1)
Exchange 2013 to Exchange 2016 Migration (Part 2)
Exchange 2013 to Exchange 2016 Migration (Part 3)
Exchange 2013 to Exchange 2016 Migration (Part 5)
Exchange 2013 to Exchange 2016 Migration (Part 6)
Exchange 2013 to Exchange 2016 Migration (Part 7)

Instant Solution - Kernel Migrator for Exchange

Exchange/Office 365 migrations are quite easy with professional tools like Kernel Migrator for Exchange. This tool helps to manage mailbox and public folder migrations involving different Exchange versions and deployment types. Also, this tool helps with all tasks starting from the pre-migration analysis to the preparation of reports after the migration.

This section deals with the process of migrating data. We will first show you how to create a mailbox database and then how to move mailboxes and public folders to the new Exchange Server 2016.

Renaming and moving the default Exchange Server 2016’s mailbox database

When Exchange Server 2016 is installed, it creates a default mailbox database in the C drive of the system. Instead of keeping the database in the default location (C drive), we need to move it as only OS should be installed in the ‘C’ drive.

Firstly, find the name of the default database. To do this, run the following command:

Get-MailboxDatabase -Server keshav-ex16

Note the name of the database from the output of the command. In our case, the database is named as “Mailbox Database 3020345612”.

Now, we will rename the database:


To rename the database, run the following command:

Set-MailboxDatabase -Identity “Mailbox Database 0939112263” -Name EX16DB

The database has to be moved now. Use the command below to move the database EDB file to “D:\Microsoft\Exchange Server\V16\Mailbox\ EX16DB.edb” and the logs to “D:\Microsoft\Exchange Server\V16\Mailbox\ EX16DB

Move-DatabasePath -Identity EX16DB -EdbFilePath “D:\Microsoft\Exchange Server
\V16\Mailbox\ EX16DB.edb” -LogFolderPath “D:\Microsoft\Exchange Server\V16\Mailbox\ EX16DB”

Creating mailbox databases

The size of the non-replicated mailbox databases should be no more than 200GB, and the size of the replicated mailbox databases cannot exceed 2TB. Therefore, we may need additional databases.

We will create another mailbox database with the below settings:

Name: EX16DB2

The new database will be created in the same place where the old database was kept: “D:\Microsoft\Exchange Server\V16\Mailbox\EX16DB2.edb”. The Log folder path will also be in the same place: “D:\Microsoft\Exchange Server\V16\Mailbox\”

To create the new database and the log files, run the following command:

New-MailboxDatabase -Server keshav-ex16 -Name EX16DB2 -EdbFilePath “D:\Microsoft\Exchange Server
\V16\Mailbox\ EX16DB2.edb” -LogFolderPath “D:\Microsoft\Exchange Server\V16\Mailbox\”

After you have created the database, the information store has to be restarted. Run the following command to restart the information store:

Restart-Service MSExchangeIS

Now that the new mailbox database has been created, we can mount it:

Mount-Database EX16DB2

Moving Exchange Server 2013 mailboxes to 2016

Moving Exchange Server 2013 mailboxes to 2016 will create a lot of logs, so it is important to ensure that you have enough space for storage. It is also wise to take regular backups so that in the case of a database failure, you can use the backups to restore the database immediately.

We will move the following types of mailboxes: Arbitration mailboxes or system mailboxes, user mailboxes, public folders, and archive mailboxes.

Move Exchange Server 2013 System Mailboxes to Exchange Server 2016

Installing Exchange Server 2013 server created a number of system mailboxes, also called arbitration mailboxes, in the database. To generate the list of such mailboxes, you will have to run the following command:

Get-Mailbox –Arbitration

These Arbitration mailboxes will have to be moved to the new Exchange Server. To move the mailboxes to Exchange Server 2016 mailbox database (EX16DB2), the following command has to be run:

Get-Mailbox -Arbitration | New-MoveRequest -TargetDatabase EX16DB2

To confirm whether the mailboxes have moved or not run the following command:

Get-MoveRequest | Get-MoveRequestStatistics

After you are sure that the mailboxes have been moved, you then can migrate the Public Folders.

Moving Public Folders to Exchange Server 2016

In older versions of Exchange, a replication problem meant moving Public Folders was a complicated process. Luckily, due to architectural changes, moving Public Folders has become much easier. Firstly, get a list of all available Public Folders on the old Exchange Server using the following command:

Get-Mailbox –Server Keshav-ex13 –PublicFolder

In our case, the name of the Public Folder is “Public Folders1”.

Now, the task is to move the Public Folders to the new Exchange Server. For that, the following command has to be used:

New-MoveRequest PublicFolders1 -TargetDatabase EX16DB2

Moving User Mailboxes

There are many different options for migrating user mailboxes. You can move a single mailbox, all mailboxes in an OU, or the entire mailbox database (if granular migration is not required). Using the commands below will move the primary User Mailboxes along with their Archive mailboxes. For those who want to move the primary mailboxes only, you can use the “ArchivesOnly.”

In our case, we will move all the mailboxes from the old Exchange Server 2013 database (“Mailbox Database 0939112263”) to the Exchange 2016 database (EX16DB2). For that, use the following command:

Get-Mailbox -Database “Mailbox Database 0939112263″ | New-MoveRequest -TargetDatabase EX16DB2

Know the status of the move request

To know the status of the mailbox move request, run the following command:

Get-MoveRequest | Get-MoveRequestStatistics


In part 4 of this series, we covered the process of creating mailbox databases on our Exchange Server 2016 and moving the system mailboxes, user mailboxes, and public folders. We have also shown you how to move all the mailboxes together.

We are almost there. In part 5, we will detail how to migrate the email flow from the old server to Exchange 2016.


Q. Is it necessary to rename the default database in Exchange Server 2016?

A. No, it is not necessary to rename the default database, but you can rename it for easy identification and management.

Q. What does the arbitration mailbox perform in Exchange Server?

A. Arbitration mailboxes are the system mailboxes that store the organizational data like audit logs from the administrator, eDiscovery search metadata, Unified Messaging Data, and custom greetings. There are multiple types of arbitration mailboxes that you should manage according to their roles.

Q. Should I create more than one database?

A. You should only create the database as per your requirement. If there are multiple databases in Exchange Server 2013, then you should create the same number too.

Q. Can I create a new public folder in Exchange Server 2016?

A. If you do not want to migrate the existing public folder, you can create new public folders.

Q. Does Kernel Migrator for Exchange migrate public folders?

A. Yes, the software can migrate the public folder between the Exchange Servers.

Q. Can I schedule the migration of public folder data?

A. Yes, the software has the facility to schedule the migration. You should specify the time after choosing the public folder, and the software will take care of the rest.