Migrate multiple mailboxes to Office 365 with EdbMails
EdbMails is an efficient and user-friendly tool for the migration of multiple mailboxes to Office 365. High-level functionalities such as concurrent migration of multiple mailboxes, auto throttling management of Office 365, incremental migration and auto mapping of mailboxes have been included to smoothly migrate from the source mailbox account to the target mailbox account.

What is Multiple Mailbox Migration?
Office 365 multiple mailbox migration is defined as a comprehensive procedure of migrating multiple mailboxes, i.e., primary, public folder, archive, emails, calendars, contacts, and their other associated information from Office 365 into an on-premises Exchange server or into an IMAP-accessible server or when consolidating multiple Office 365 tenants into one common mailbox location. By using EdbMails for this purpose, you would be able to run parallel migrations. So, it would become quite easy to migrate each mailbox within the entire organisation in less time. To put in simple words, EdbMails is a very efficient application for improving the performance of mailbox migration.
Now let's take a look at some of the significant features and benefits EdbMails Office 365 migration software provides and see how the software streamlines multiple mailbox migration.
Multiple Office 365 mailbox migration - Pre-migration activities
On source Office 365 server:
- Make sure you have a Global Admin account with a mailbox for Auto Registration of the EdbMails application on your Entra ID (Azure Active Directory). For Manual Registration, you can use either a Global Admin account or a user account with full access permissions.
- Ensure that your network and bandwidth meet the requirements for the migration.
See network and migration planning, performance factors and best practices for Office 365 to Exchange migration.
On target Exchange server:
Step 1: Check that your system meets the Exchange server setup requirements.
Navigate through the below links to set up your target Exchange server environment based on the Exchange version you want to migrate to. Learn more about the network, hardware and operating system requirements for installing Exchange server.
- Exchange 2013 Server setup
- Network and directory requirement for Exchange 2016
- Network and directory requirement for Exchange 2019
- Hardware Requirements for Exchange 2016
- Hardware Requirements for Exchange 2019
- Supported operating systems for Exchange 2016
- Supported operating systems for Exchange 2019
Step 2: Prepare your target server with the following prerequisites
Complete the following prerequisites for Active Directory, Windows Mailbox server, and Windows Edge Transport servers before installing the Exchange server.
- Exchange 2019 prerequisites for preparing Active Directory (AD)
- Windows Server prerequisites for Exchange 2019
- Exchange 2016 prerequisites for preparing Active Directory (AD)
- Windows Server prerequisites for Exchange 2016
Step 3: Set up Exchange Server for migration
Given below is a list of key points for installing and preparing the Exchange server for migration.
- Prepare AD and domains
Before installing Exchange Server you need to prepare your Active Directory forest and its domains for the new version of Exchange.
If you have a separate team to manage the Active Directory schema, you need to first extend the active directory schema, else proceed to the next step to prepare the Active Directory.
If you have multiple domains you need to additionally prepare the Active Directory domains.
- Install Exchange server on your computer
Before installing the Exchange server, ensure that you meet the system requirements and prerequisites as outlined previously. Next, follow the link to install Exchange 2016 or install Exchange 2019 from the setup wizard.
- Prepare a clean Exchange target environment
- Create and configure a Send connector to send mail outside the Exchange organization.
- By default, Exchange automatically creates receive connectors for inbound mail flow when the mailbox server is installed. If you need to configure receive connectors, follow the steps in the link.
- Add accepted domains to allow recipients to send and receive email from another domain.
- Configure the default email address policy to add the accepted domain to every recipient in the organization.
- Configure external URLs (domains) on the virtual directories in the Client Access (frontend) services on the Mailbox server to allow clients to connect to your server from the internet (outside the organization’s network).
- Configure internal URLs on the virtual directories in the Client Access (frontend) services on the Mailbox server to allow clients to connect to your server from the internal network.
- Configure SSL certificates from a third-party certificate authority for services such as Outlook Anywhere and Exchange ActiveSync.
- Verify the Exchange server installation by running the command Get-ExchangeServer on the Exchange Management Shell (EMS).
Verify the mailbox of the admin account
Check to see if the admin account that has been assigned management roles has a valid and non-hidden mailbox on the Exchange server.
Settings related to throttling and message-size limits
- If Microsoft throttles the migration, change the EWS throttling settings on Exchange server.
- If the migration is stuck due to the large size of a message, set the message size limits to the maximum on the Exchange server.
Step-by-step guide for Office 365 multiple mailbox migration with EdbMails
In this guide, we'll walk you through the process of migrating multiple mailboxes to Office 365 using EdbMails Whether you're migrating from the same domain or different domain, this step-by-step approach ensures a seamless migration experience with the software. From initial setup and data migration to monitoring progress, this guide will cover all the essential steps for a successful Office 365 mailbox migration.
Step 1: Download and Install EdbMails application
- Download and install EdbMails software on your system
- Click ‘Login’ or ‘Start Your Free Trial’ to get started with EdbMails.
- Check system requirements for Office 365 migration.
Step 2: Select Office 365 to Office 365 migration option
- Select the 'Office 365 Migration' option
- Select ‘Office 365 to Office 365 Migration’.
- Keep the default job name, or click ‘New Job’ button to change the job name.
Step 3: Connect to source Office 365 server
- Click ‘Add New Connection’ to set up a new link to the source Office 365 account. To reuse an existing setup, choose it from the list and click ‘Connect to Existing’.
- Choose the required connection options and click the ‘Next’ button.
- Select one of the secure OAuth 2.0-based modern authentication methods and authenticate Microsoft sign in page
- Click the ‘Login’ button to continue.
- After authentication, select a method to load mailboxes or use a CSV file to import them for migration.
- Select the multiple mailboxes you want to migrate from the source Office 365 server.
- Click ‘Next’ to proceed.
Step 4: Select Office 365 Mailboxes
- Click ‘Add New Connection’ to connect to the target Office 365. To reuse a saved connection, select it from the list and click ‘Connect to Existing’.
- Choose the desired connection options and click ‘Next’ to continue.
- Choose the appropriate target connection method and authenticate on Microsoft sign-in page.
- Click the ‘Login’ button to continue.
- Choose the one of the methods to load all mailboxes.
Step 5: Map source and target mailboxes
- Choose the required mailbox mapping option
- Once mailboxes are created on the target server, EdbMails automatically maps mailboxes and folders between source and target tenants. You can manually map folders and subfolders to specific target folders.
Step 6: Start multiple Office 365 mailboxes migration
- Click ‘Start Migration’ to begin the migration process.
- EdbMails will start the migration automatically and notify you when it's finished. Click ‘View Logs’ to check the migration report. You can also pause or resume the process as needed.
Post migration activities
Step 1: Update the MX records to point to Office 365
Add a domain to Office 365. If you never modify DNS records, then update MX records to have emails route to Office 365. You need to add Autodiscover records so that Outlook will connect to mailboxes being moved to Office 365.
Step 2: Clear the Auto-Complete list in Outlook
See manage suggested recipients with Auto-Complete.
Step 3: Create a new Outlook profile after migration
- All users have the latest available version of Outlook installed to prevent compatibility issues.
- Create an Outlook profile for all users within your domain if users encounter issues connecting to Office 365 mailboxes.
- Set up Outlook with the new server parameters (server address, user name, and password).
- Check the email function works so the user can now send and receive email.
Step 4: Remove the old Office 365 subscription plan
After migration is done and data integrity for the migrated mailbox can be assured, you can delete the Office 365 subscription plan and its domains from the source tenant.
After all migration is done and you have verified that the data of the migrated mailbox is intact, disable/delete the Office 365 subscription plan and all associated domains from the source tenant.
Benefits of EdbMails for Office 365 multiple mailbox migration
- Intuitive Office 365 migration interface
EdbMails provides a user-friendly software interface that allows you to complete the migration process in a few clicks, thanks to automation that automatically loads the mailbox from your Office 365 server and maps it between the source and target servers, saving time and manual work. You do not require any highly technical skills to perform the migration with the help of the software.
- Automatic mailbox loading from Source and target servers
EdbMails also provide a feature to load mailboxes automatically from your source and target servers. This feature will be particularly helpful to small organisations with 100 or fewer mailboxes, as it eliminates the need for manual effort. For larger numbers of mailboxes, it is possible to load mailboxes using the CSV method.
- Free from Office 365 Throttling during migration
With Automatic Throttling management in EdbMails, there is no compromise with data migration between the Office 365 servers during peak and off-peak hours. This functionality removes manual waits and restart operations, which can be really helpful when you are moving a large number of mailboxes. This will avoid data loss and duplicity on the target server and thus save your effort and time during the migration process. Additionally, EdbMails helps prevent server hang-ups and ensures no server downtime during migration.
- Optimised Performance and Speed
EdbMails enables concurrent mailbox migrations, thereby improving the speed of migration as the migration can occur for a larger number of mailboxes together. It allows performing 10 simultaneous migrations, but the limit of simultaneous migrations is raised to 20 mailboxes to achieve a higher speed of migration. Moreover, EdbMails can be installed on many machines and can migrate the distinct mailboxes to improve the speed of migration.
- Zero-Downtime while Migrating to Office 365
EdbMails ensures Zero Downtime during your entire Office 365 migration, even during working hours. With the EdbMails migration process, the mailboxes will keep functioning without interruption. Mailboxes can continue to work from the source mailboxes till the time the entire mailbox is migrated. They can then resume working from the destination Office 365 tenant as soon as the migration is completed.
- Ensures Office 365 data Integrity during migration
While migrating to the target server, EdbMails will retain source mailbox data and ensure you with total migration of all mailbox elements, namely E-mails, attachments, calendars, contacts, etc. Hence, you can remain assured that nothing is lost/damaged during the migration.
- Securely migrates Office 365 mailbox data
EdbMails migrates your data using Microsoft's secure APIs and performs the migration according to Microsoft's prompted migration flow. The credentials you entered will not be saved on our servers, nor will your data. Your Office 365 credentials aren't saved and protected by OAuth 2.0 and TLS encryption during authentication. This software takes advantage of modern authentication method; MSAL (Microsoft Authentication Library and Microsoft Graph) & OAuth 2.0 are secure authentication methods for accessing your Microsoft Office 365 account.
- Support for all Office 365 Migration Methods
EdbMails assists all the possible Office 365 migration methods like cutover migration where entire mailboxes are being migrated all together or a staged migration, allowing migration for a batch of mailboxes. With the help of the above methods, an organization can opt for the method that suit their migration and need their requirements. Migrating few mailboxes or more number of mailboxes, EdbMails has an array of solutions to conduct successful Office 365 migration.
- Comprehensive Migration Reporting
The EdbMails provides a comprehensive Office 365 migration report for showing the in-depth analysis for the mailbox migration along with the mapping details. You can track the migration status of the every mailbox along with the count of the migrated folders and verify item counts, ensuring the integrity of the migration process.
- Cost-Effective Office 365 Migration solution
EdbMails offers an economical pricing plan to ensure your Office 365 migration can be implemented easily and without exceeding your budget. The system is on the basis of the count of source mailboxes which allows you to control your financial outflow. Our adaptable lifetime subscription plans allow for changes in the amount of users in correspondence with growth in business. Also, a 24/7 tech support and free software updates are provided with the software.
Frequently Asked Questions
How to perform Office 365 Multiple mailbox migration with EdbMails?
- Step 1 : Download and Install EdbMails software
- Step 2 : Select the ‘Office 365 Migration’ option
- Step 3 : Connect to Source Office 365 server
- Step 4 : Select multiple mailboxes for the migration
- Step 5 : Connect to target Office 365 server
- Step 6 : Select the required mapping option and start migration
What are the benefits of multiple mailbox migration for Office 365?
There are several strong advantages in migrating multiple mailboxes to Office 365. One of the major advantages is faster mailbox migration efficiency where it allows the migration of multiple mailboxes simultaneously, thus drastically minimizing migration time. Users will be able to access their mails during migration with zero downtime.
This approach is highly scalable and flexible, and will fit organisations of any size. Administration becomes easier because of centralization of the migration management, streamlining administrative tasks.
Moreover, multiple mailbox migrations ensure the data consistency between the source and target environments and maintain data as source and target, along with the data integrity. This ultimately contributes to financial savings, increased operational agility, and a seamless and effective move to Office 365 and, by definition, can bring other benefits too.
Is there a limit to the number of mailboxes I can migrate?
EdbMails also facilitates the migration of bulk mailboxes at the same time, thus let you migrate data efficiently from Office 365 server. This means you can parallelly migrate 20 mailboxes by EdbMails which helps in performing the migration more effectively.
Though EdbMails allow you to migrate multiple mailboxes at once, but the actual numbers you can migrate depend upon number of mailbox licenses you own from EdbMails.
Click here to know the details of used and unused licenses from the EdbMails Office 365 migration window
Does EdbMails provide reporting for migration status?
Yes, EdbMails includes granular reports on migration status, which details count of migrated items and source to destination mailbox mapping. While migration is being done, EdbMails will give you updates with the number of item transferred, ensuring you have a clear understanding of the data transfer.
While the migration is in process, EdbMails provides reports on the migration progress that show how many items were migrated.
Moreover, you can review the mapping between source and target mailboxes with EdbMails which ensures the data is migrated with right precision. With this reporting ability you can track the migration status in real time, allowing you to react if there are any problems to make it a successful migration experience.
Is EdbMails suitable for businesses of all sizes?
Yes, EdbMails can perfectly suit for the all types and sizes of businesses. EdbMails is versatile in nature and compatible with all small, medium, and large sized business environments. Whether you have loads of mailboxes to be managed or migration project requiring hundreds of users, EdbMails fits all your needs. The small business gains from its easy-to-use interface and cost-effective options, while the large business benefits from scale, the support for concurrent migrations, and powerful reporting capabilities.
What kind of support does EdbMails offer during migration?
EdbMails has complete support to carry out an Office 365 migration smoothly. The customer support executive is always present in 24x7 availability. They resolve issues and help out with migration needs. In addition, EdbMails provide many helpful resources, like documentation, instruction guide, email support, live chat support, tutorial, FAQ and knowledge base, all aimed at providing users with the detailed information and assistance.









