In most companies today, email is a critical business tool, but all too often, companies fail to take a strategic approach to managing it. At the same time, many companies value the central coordination and address management available with Microsoft Exchange but don't want to run a mail server 24x7.
With Microsoft Office 365, Microsoft has entered the hosted/cloud email hosting market, and it's now among the company's fastest-growing products. As with any such changes, though, it's important to do the Office 365 migration right; email communication is too critical to put at risk. Companies need to plan their migrations carefully and pilot-test and verify at every step.
Examining email strategies
The dominant business email strategies in place today include standard (Internet or in-house Apache) email hosting, Exchange hosting or running an in-house Exchange server. The best approach for migration varies among those strategies; in some cases, it may mean migrating separate groups of email users in different ways with different tools.
For an Exchange user, the first consideration is SharePoint migration. Here the question is whether the company has customized SharePoint on its own or if its reseller has done it on their behalf. In cases where customization has been done for them, companies need to either fall back to a vanilla SharePoint Online or run their customization in Windows Azure, Microsoft's cloud. Some custom tools (AviPoint, MetaVis, Quest and others) will migrate a current SharePoint structure, including (in most cases) metadata, to SharePoint Online.
Companies need to plan their Office 365 migrations carefully, and pilot-test and verify at every step.
For companies that obtained Exchange through resellers, the first step should be contacting the reseller to see whether it has specific tools to facilitate migrating to Office 365. Microsoft has its own set of online resources and tools, but companies that have worked with resellers will find that those resellers know their set-ups and have special tools available to facilitate migration. In addition, Microsoft has encouraged its resellers to migrate from providing Small Business Server to offering their own Office 365 toolkits.
The second step is to establish the Active Directory linkage for Office 365 and other applications for use with single sign-on (SSO), if applicable. The challenge here is that Active Directory will still have to be maintained on premises, which requires federating the sign-on with Office 365 and also supporting the other applications. Companies that aren't using Active Directory now may not want to jump into it internally at the same time they're contemplating migrating to Office 365. At the least, it means losing the cloud-only model that they may be seeking. Companies may wish explore other popular single-sign-on models for Microsoft's applications (Centrify, Okta, Ping) if they want SSO capability, especially if they're moving to a cloud-only architecture.
In cases where organizations already have hosted Exchange from third-party providers, it's best to check the host's documentation to see how it supports a migration between the hosted service and Exchange, and then treat the migration to Office 365 as an Exchange migration. The challenge organizations may face here is that the administrative processes available for an internal Exchange migration may not all be available in the hosted version. Users report that their hosted Exchange providers generally don't support their desire to migrate to Office 365, so don't expect much help directly from providers. However, many of the third-party tools listed earlier to facilitate SharePoint migration or SSO may be helpful.
Getting individual users migrated is facilitated by exporting the email and other data in the form of a PST file (in Outlook) for re-importing in Office 365. This mechanism nearly always works, but it requires a clean cutover between the hosted version of Exchange and Office 365. It's best to do that over a weekend or holiday period, when users can afford to be without email for several days while the new setup is being populated and validated.
Meeting Office 365 migration hurdles
The biggest challenge in migrating to Office 365 comes for companies that aren't Exchange users at all. In those cases, there's a two-step process. The first is setting up the Office 365 hosted Exchange environment with SharePoint and SSO/Active Directory as needed; the second is the mailbox migration. For the first step, it's best to consult standard books and tutorials on Exchange for the setup, and take the time necessary to establish and test the Office 365 configuration with some dummy mailboxes and user accounts first.
Migrating the users from POP3 or IMAP clients to Office 365 can be a truly knotty problem. For Outlook users, the approach of creating a PST file for transferring mail and address books is fairly straightforward. For those who don't use Outlook, the problem is likely to lie in the difficulty of getting this information moved. Anyone who has used multiple email clients has probably already encountered the low level of compatibility between them, and mailbox conversion tools are available, their value differs depending on what features are used and what mail clients are involved. The best recommendation from users is to secure several Outlook licenses and migrate first to Outlook, check the results of the move, and then migrate from Outlook to Office 365 using the processes described above.
The most important point in migrating to Office 365 is to pilot-test, migrate and verify at every step of the process. No tool or procedure should ever be applied on live data without having checked it first with a contained set of test accounts populated with representative email samples and address book entries.
Also remember that the final step is to validate the mail settings themselves and the shared resources (Active Directory or other SSO, SharePoint, folders and file structures, etc.) before moving on to working with live data. Migrating users in groups (by department, for example) can also ease the burden of migration and get users who interact regularly all moved at one time. A little planning will go a long way in securing a successful migration, and many users say Office 365 is worth the effort.