How to Overcome the Office 365 Migration Challenges?
Migrating to Microsoft 365 (formerly known as Office 365) from on-premises Microsoft Exchange Server or IMAP-based email system is a complex task. It requires extensive planning, preparation, and knowledge to begin with. It also requires expertise in handling and moving the mailboxes and other data securely to the destination server during migration. There are various methods to migrate mailboxes from on-premises Exchange to Office 365.
However, there are certain challenges and limitations associated with the on-premises Exchange to Office 365 (Exchange Online) migration methods. In this article, we have discussed the challenges associated with these methods and the ways to overcome these challenges to ensure smooth and error-free migration to Office 365.
Office 365 Migration Methods and Challenges
To migrate mailboxes from on-premises Exchange Server to Office 365, you can follow the below methods based on your Exchange Server version and requirements.
· PST Import
Below we have discussed these migration methods, the challenges (limitations) associated with these methods, and solutions to overcome those challenges.
Cutover Migration
Cutover Migration, also known as Express Migration, allows administrators to migrate mailboxes from Exchange Server 2003, 2007, and 2013 to Office 365. You can perform the migration using the Exchange Admin Center (EAC).
However, there are several limitations and challenges associated with this method, such as:
· You can use this method only if the Exchange organization has fewer than 2,000 mailboxes to migrate to Office 365.
· You cannot migrate mailboxes from Exchange 2016 or 2019 to Office 365 using this method.
· Cutover Migration is a long process that requires significant time. Thus, it requires planning and time estimation before starting, as it can take days to complete the migration.
· You should create and migrate 150 or fewer user mailboxes at a time using the Cutover Migration method to avoid issues.
Staged Migration
In Staged Migration, the administrator can migrate the contents of the user mailboxes from an on-premises Exchange Server 2003 or Exchange Server 2007 to Office 365 over time. For example, you can move or migrate more than 2,000 mailboxes from on-premises Exchange Server to Office 365 in two stages.
· First Stage: Contents of the mailbox are moved over time, MX records are updated, or the domain is transferred to the destination server. Also, newer data is moved from Exchange to the Office 365 mailbox. This allows users to access and continue using their email accounts while the remaining data is being migrated.
· Second Stage: In this stage, the remaining mailbox data is migrated to the target server.
Below are the challenges associated with this migration approach:
· You cannot migrate mailboxes from Exchange 2010 or later using this method.
· You must sync the Active Directory domain on on-premises Exchange and Office 365 using the Azure Active Directory Sync. Otherwise, the Staged Migration won’t work.
· Users must create and set up the account under a new profile to connect to their mailboxes on Office 365 or Microsoft 365.
· This is a time-consuming process. Also, this may not work in some situations.
· Once the migration is complete, you need to assign licenses to each user in Office 365 to allow users to log in and access their mailboxes.
Hybrid Migration
Hybrid Migration is required when you maintain both on-premises and Office 365 mailboxes in your organization. In this process, you gradually migrate the mailboxes, including all emails, contacts, calendar items, etc., from an on-premises server to Office 365 or Microsoft 365. Microsoft Exchange Server 2010 or later supports Hybrid Migration where you need to move 150–2,000 or more mailboxes.
The administrator doesn’t need to create user mailboxes on the destination server or import information. Administrators can migrate mailboxes or data between Exchange and Office 365 easily.
However, this migration method only applies to Hybrid Exchange environment and does not support Exchange Server 2007 or earlier versions. Also, you need to purchase the Office 365 plan that supports Azure Active Directory (AAD) Synchronization. Office 365 Home and Business plans do not support the AAD synchronization.
PST Import
PST import is a popular migration method that allows Exchange and non-Exchange Server users to migrate their mailboxes to Office 365. In this method, the PST file is uploaded to Azure Storage and then imported into the user mailboxes on Office 365.
You can convert user mailboxes into PST format in Exchange using the Exchange Admin Center (EAC) or New-MailboxExportRequest cmdlet in Exchange Management Shell. In addition, if an account is configured in Outlook, you may export the mailbox to PST format using the Import Export wizard.
Once you have the PST files, you can upload them using the Azure AZCopy tool or ship them in a BitLocker-encrypted hard drive to Microsoft. You also need to create a CSV mapping file to map PST files with user mailboxes on Office 365 before starting the import wizard in Office 365.
The challenges and limitations of the method are as follows:
· You need to manually create or export mailboxes to PST files for each user and then upload them to Azure Storage or ship them to Microsoft.
· If you choose the PST shipping method, you will have to shed $2/GB or $2000 for 1000 GB.
· Data security is another challenge.
· Requires CSV mapping file.
· Before mailbox mapping, the user mailboxes must be created in Office 365 with assigned licenses.
IMAP Migration
You can use the IMAP migration method if you need to migrate mailboxes from IMAP-based email servers. It works with all IMAP-based servers without any mailbox limit.
However, in this method, only the mail items in the Inbox and other mail folders are moved or migrated to Office 365. Other items, such as calendar items, contacts, tasks, notes, etc., are not migrated.
Also, you will have to create user mailboxes on Office 365 and assign licenses first before using the IMAP migration as you cannot create mailboxes on Office 365 during migration.
Other Challenges with Office 365 Migration
In addition to the specific limitations of Office 365 migration methods, you may encounter some other challenges.
Network Issues and Bandwidth Concerns
In Office 365 migration, you move the mailboxes from an on-premises Exchange Server to the cloud. Thus, it requires high bandwidth and stable network connection to ensure smooth migration. Network or connection issues may break the migration leading to extended downtime and additional costs to the company.
Connectivity errors can lead to issues, such as AAD synchronization, inaccessible Office 365 tenant, etc. You also need to ensure that your network plan is fast and has ample bandwidth to transfer a large amount of data (mailboxes). If the bandwidth is consumed, you may fail to move mailboxes.
To avoid bandwidth-related issues, you may increase it or migrate the mailboxes over days as the bandwidth renews. However, if there are terabytes of data you need to migrate, it will take a lot of time.
Security and Compliance
User mailboxes contain confidential business data and private information. Thus, while migrating such a large amount of sensitive data, it is important to keep data security and compliance in mind. In addition, you need to make sure that the data is transferred over a secure network. Also, clean up old or inactive mailboxes and obsolete data. Avoid moving such data as this will help save you time and cost.
Subscription Plans
Office 365 offers several plans. You must choose the plan that meets the requirements. Based on the number of mailboxes and average size, you can choose the plan and add more storage.
Final Thoughts
In this article, we have shared the methods and challenges associated with the various Office 365 migration methods. We have also discussed some common challenges associated with the methods. Fortunately, you can avoid and overcome these challenges associated with Office 365 migration methods, with the help of an EDB to PST converter software, such as Stellar Converter for EDB. The software can help you move all the mailboxes from your on-premises Exchange database file (.edb) directly to Office 365.
The software uses Microsoft Modern Authentication method to connect with the Office 365 tenant, auto-maps the source and destination mailboxes, and provides option to prioritize the mailboxes export. All your data is securely migrated to Office 365 tenant with complete integrity and precision.
