The technical part of a migration to any new technology is usually straightforward and hopefully well documented. If you’re moving to Office 365, there are a number of Microsoft resources and third party migration tools like SkyKick, BitTitan and Sharegate to do the actual “lifting and shifting” of your data into the Cloud. We like to think that we’re all special, but a mailbox is just a mailbox.

Why then do consultants quote so many hours and hundreds of dollars per mailbox for an Office 365 migration? Because the main effort goes into the pre-migration planning and clean-up.

An organization’s email system and authentication directory can evolve over time, especially in the SMB market if they started out as a very small (micro) business. IT people have different ways of doing things. End users have their own ingrained habits regarding email use. But not all processes and habits translate well to the Cloud.

Before your Office 365 migration, watch out for:
Sharing user accounts – “They are only temporary staff and they share the same computer.” In the real world, this happens, especially in organizations with casual, seasonal staff or shift workers. In the Microsoft Online Services world, they are two people and they’ll each need their own User Subscription License. End of story. This applies if they only access the same Shared Mailbox (which doesn’t need a separate license itself). It also applies if their license allows them to install Office on 5 computers – that’s 5 computers that they use, not that other people are using their license on. Many smaller organizations try and save themselves a few dollars here and the Microsoft licensing audit team really doesn’t like it.

Folders, folders everywhere – Most organized people like to move emails into folders. When that love of folders gets out of hand, you’ll start to have problems in Office 365. 500 folders or more creates performance issues and sync problems in Outlook’s cached mode. The workaround to not cache these mailboxes locally leads to user frustration with the overall performance of Outlook, unless you’re on a very good Internet connection. This is common with personal assistants opening the boss’ mailbox and an accounts department managing both accounts payable and accounts receivable communications in the same mailbox. The best workaround? Reduce the number of folders in the mail file and develop new filing habits.

The opposite of organized – On the other end of the scale are people who have never heard of folders. Their mode of operation is to keep everything in one of two places – either their Inbox or their Deleted Items “folder”. Don’t you ever empty their deleted items, that’s their archive! This kind of email habit will see you frustrated with search and sync response times (too many items in one folder). The default Office 365 policy also does like to clear out those Deleted Items regularly, so it’s time to teach these users some new email behaviours.

Backing up PST files – If your existing system is an on-premises Exchange server, you hopefully have a backup system that’s backing up your mailboxes while Exchange is running. If you’re using another e-mail system, you might have been creative with your backup solution. Commonly with IMAP or POP systems, admins create PST files and back these up. With Office 365, the PST file is dead. This standalone file can be easily corrupted and you end up with a mass of individual files to manage. Don’t try and squeeze Office 365 into your on-premises backup system. If you’re after an independent backup outside of the Microsoft Cloud, there are third party providers like SkyKick and Storage Craft that backup straight from Office 365 to their own Cloud and provide simple recovery interfaces. You’ll recover the cost of this kind of solution in the time it will save you managing backups & restores.

Fragmented, outdated Active Directory –  Now I know your Active Directory is in great shape. That might not be the case if you’ve inherited it from somebody else. It could be full of fragmented OUs, users that have left the organization etc. Microsoft will recommend that you sync your Active Directory to the Cloud, and there are many identity management and sign on benefits to doing that (even with Azure AD Connect). However, connecting a messy AD to Office 365 is not a good move. Spend some time tidying up your AD first. It’s better to connect a clean AD to a new Office 365 tenant than it is to put this off, create new Office 365 users and try to connect everything in the future. Technically it’s possible, but starting with a clean, connected AD will cause you the least amount of problems.

These are just some of the main pitfalls that I’ve seen organizations fall into with their Office 365 migrations. Don’t assume that a new email system will magically solve all of your problems. With bad habits, it’s quite easy to migrate your problems too!