Office 365 Email Migration: 10 Steps To Ensure a Smooth Process

Office 365 offers a variety of robust features and programs for personal and professional use. Adopting a SaaS (software as a service model), 365 allows users to integrate their work, files, and programs in an accessible location, usable from any compatible device, any time of the day. Traditionally, most businesses rely on mail systems situated on an Enterprise server, and while effective, modern demands mean newer and more efficient ways to communicate are required.

Today, organizations are using it for its powerful email service, upgrading from old communication infrastructure to new. If you’re looking to do the same, you can look forward to a streamlined app with lots of functionality. But, it’s a matter of upgrading first, which is easier said than done. Fortunately, we’re here to help. We’re going to take you through a quick guide to give you a set of steps to help you migrate your email and communication services to Office 365.

From our list, you’ll understand how to form a concrete plan suited for your business’ unique needs.

Getting Started

There is a multitude of approaches and criteria to follow for each business model, and all are different depending on the organization size. Tackling all of them isn’t practical, but, we can go through some core guidelines which each organization should follow. Doing so ensures a healthy Office 365 migration. Let’s break them down into steps.

1. Develop a Roadmap

As management prepares to begin the transition to 365, it’s crucial to understand both staff and organizational needs. Establishing this criterion means understanding what your business intends to use 365 for, what files will go with it, and who will access it. 365 is ultimately about streamlining your office as a collaboration platform, so get a feel for how staff will use aspects of it. Do you just need email, or more? Messaging services? Files storage? Know the answer to these questions to better help prepare management and staff for the transition ahead.

2. Select a Migration Method

Depending on what servers/infrastructure your business uses, you’ll need to select an appropriate migration method. Large businesses will face the largest challenges, as they have the most data to move, while smaller organizations will have to less to do. However, both pose their own difficulties, so it’s important to select the right method and avoid problematic headaches.

Generally, there are three known types:

  • Cutover Migration – The easiest migration method, though only suited for small organizations with 1000 or less mailboxes. Requires mail migration occur all at once, however, so not suited for enterprises looking to perform a gradual migration.
  • Next is IMAP migration. A shortcut for migrating Exchange servers – however, can only migrate mailboxes. If your business only needs to manage email communication, it’s a good choice, otherwise, try a different method.
  • The next type is hybrid migration, generally suited for organizations of all sizes, though is the most complex in nature. It requires the creation of a hybrid exchange server, establishing a link between a local one and a 365 server. While it needs experts, it’s the best method for larger businesses and organizations.

3. Prepare Infrastructure

Just like you need to ready your staff and management for the new features brought with 365, you need to make sure company infrastructure has the resources for the actual migration/setup. Think of it this way – it’s like sending supplies to a warehouse, so you need to build the road and the warehouse too.

It’s important to have proper server management resources running like Active Directory Federation Services. This will allow you to create both migration servers and perform necessary admin functions when preparing to migrate your mailboxes. You can also use virtualized services/systems, but the process is much slower. Stronger hardware and resources are generally required when migrating for larger businesses.

4. Conduct Early Tests

A nightmare scenario is migrating your infrastructure, mailboxes, calendars, and service to the 365 cloud, only to discover a forest of problems. The migration process is time-consuming and can vary based on the size of your business/needs. Therefore, we recommend conducting tests before dedicating serious time to service migration. Migrating test emails to view the success (or failure) of their functionality will let you know if early problems are occurring.

5. Create Use-Case Guidelines

As you start to ready infrastructure and define how users will interact with 365, take some to establish guidelines. This is important, as it maintains diligent record keeping and a secure approach to utilizing the software. For instance, when using Office 365, how will staff send and store messages (if they do)? What’s a record-keeping strategy? What programs are used during a normal workflow?

Migration is only one step of the process – how you use Office 365 will determine its effectiveness.

6. Check Your Exchange Version

During migration, you’re shifting mailbox infrastructure from an Exchange server to the Office 365 cloud server. A newer version of Exchange will generally not have compatibility issues. Older ones, however, may present problems (such as Exchange 2003/2007). For example, during migration, a business will lose access to mail services with older Exchange versions. A way to work around this is to update the Exchange version to a newer one and then migrate to Office 365 from there.

We strongly recommend this, as issues with older Exchange versions can create even longer migration periods.

7. Check Readiness with Office 365 Health

As you prepare your servers and staff for the migration process, it’s critical to assure the infrastructure is readyIt’s why we recommended conducting tests to see how migration affects your emailYou can do this using one of Microsoft’s tools: Office 365 Health. This program can conduct comprehensive tests to ensure every part of your migration process is ready. You have options for a quick or complete check – the latter more time-consuming.

It’s strongly recommended to do this before engaging in your mailbox migration. In fact, we view it as mandatory.

8. Compatibility Check

Just as with older Exchange servers, you need to be sure all your applications are compatible with Office 365, especially with Outlook. Outlook has a variety of older mailing versions. Some of them don’t work with 365, so you’ll need to comb through the company network to be sure migration won’t affect compatibility.

9. Use Helpful Resources

Though is process can be complex based on the volume of mailboxes requiring migration, there’s nothing stopping your organization from taking advantage of the various tools and resources to assist with Office 365 email migration. Microsoft provides free utilities, such as the readiness tool, and others like the Exchange Server Deployment Assistant. You can also utilize third-party tools and resources, but know those are normally costly.

Examples are tools like MetaLogix or Sharegate.

10. Plan Your Migration

Now that you’ve established a roadmap for your migration, you need to decide what format works best. Generally, we recommend a staged migration process instead of migrating email services in one go. This is because, during said migration, those services are unavailable, including critical systems used by administrators and management.

Staged migration even allows for Office 365 and Exchange servers to work together. In some cases, this can be permanent (though we ultimately suggest making a complete transition to 365 for compatibility reasons). However, multiple servers add to the complexity of maintaining infrastructure, while also including the likelihood of compatibility problems.

Once you settle on a migration method, you can begin transitioning from Exchange servers to Office 365. Take as much time as needed to set up appropriately before commencing – the more planning is done the less chance there is of downtime, restarts, and progression loss.

Remaining Tips

You should have a better idea of how to best enact a migration strategy. Before you wrap up, here are a few final tips to remember:

  • Know the roles in your organization and how staff will use Office 365.
  • Adopt a record-keeping strategy after migration, along with backup options if needed.
  • Only install additional customizations compatible with Office 365. Additional add-ons may disrupt services.
  • Adopt easy one-click sign-ins, allowing for easier user integration. This will save your staff a lot of headaches down the road.
  • Clarify ahead of time why your enterprise is shifting to Office 365, and help staff understands their position as you transition to the cloud software.


While upgrading communication infrastructure – especially email – is a time-consuming process, it’s well worth it to gain the benefits of Office 365. Microsoft’s app allows for seamless integration between programs, emails, and management solutions, expanding efficiency with both your network and project goals.

Take the necessary time to plan and set up a feasible roadmap, and your migration process will go smoothly. If you’d like an assessment or want to know more about migrating to Office 365, you can visit us at Executech.

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