Of all the Office 365 migration tasks, Exchange Online is perhaps the most important – particularly if (like most) your business runs on email. As such, a robust migration plan is essential in ensuring that the transition is carried out as seamlessly as possible, leaving productivity unaffected.

The framework should contain the following basic principles.

1. Due diligence

The key to a successful Office 365 migration is understanding your current Exchange server environment. This means assessing the readiness of both the Exchange and Active Directory configurations. This raw data must then be used to plan out every step of the actual migration, from email accounts, to message archives.

Don’t forget!

  • Document existing Exchange and Active Directory configuration.
  • Analyse Microsoft Outlook client settings.
  • Include your mobile devices and settings in the analysis.
  • Security settings for both server and clients will also need to be recorded for replication.

2. Remediation and preparation

The due diligence process will identify several issues with your current set-up that need to be resolved before you can begin migration. The specific steps required will depend on whether your business has chosen a fully-hosted or hybrid deployment. With planning complete, the next task is to configure the relevant connections between your systems and the Office 365 service. This includes configuring the Azure tenant and associated connectors (VPN, Active Directory Server and Active Directory Connector), and the Office 365 tenant. Depending on the version of Exchange in use, you may have to perform a software upgrade to ensure your environment meets the standard required for Exchange online. If you have chosen a hybrid email implementation, you will need to install Exchange 2010 or above in Hybrid mode.

Don’t forget!

  • Failing to prepare your Exchange systems in advance could result in a failed migration.
  • You will also need to migrate all of your SMTP integrated applications.
  • You should perform all of these steps on a test environment first.

3. Mailbox and service migration

With prep work and testing complete, your tech team can begin the process of migrating mailboxes and services to the cloud. Rather than implementing a system freeze for hybrid deployments, we recommend syncing 95% of each user’s mailbox in advance. In this way the switch-over is virtually seamless (nothing more than an outlook restart), and the effect on productivity is minimal. If you plan to fully retire your onsite Exchange architecture, you will need to schedule batch migration of mailboxes outside office hours.

Don’t forget!

  • Office hours for remote workers and international employees may not match up with your own.
  • Where you plan to use hosted Cloud email archiving services, the relevant data stores will also need to be migrated before taking your new Exchange Online service live.
  • You will need to ensure permissions and security settings are replicated to your new system so that email data is properly protected.
  • Test to ensure that migrated data has mirrored correctly, and that there has been no corruption during the transfer.

4. Decommissioning and troubleshooting

The final step of your Exchange Online migration plan is to decommission the outgoing system. With services, rules and data successfully moved to the Cloud, your team should be able to begin the process of retiring or redeploying old hardware.

Don’t forget!

  • Legacy systems that “break” following migration may be still be configured to use your old SMTP server settings.
  • Once testing is complete, ensure that the legacy Exchange environment cannot be reactivated.

No “one-size-fits-all” approach

The Office 365 migration will take many weeks to complete fully because no two operating environments are the same. Some organisations may find that the complexity of their current Exchange set-up and connected services requires additional resources to properly effect a move to the Cloud. For this reason we strongly recommend that any business considering an Office 365 migration seeks expert advice. When working with Active Directory and Exchange, there are a number of potential pitfalls that could derail the whole project, damaging productivity and increasing the cost of migration exponentially.

When you partner with Acora for an Office 365 migration, we will develop a custom project plan. To learn more about the Acora Office 365 migration plan and how it can save your business time and money, please get in touch.


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