The last few months have been pretty intense, but we finally finished moving ~18000 mailboxes from Lotus Notes to Office 365. I went to the first startup meeting for the implementation part of the project in late September, and we finished most of the migration this week, which was pretty satisfying to say the least 🙂

It has been a long journey (done in a short timeframe), and a lot of things needed to be done in order for it to work.

Some of the obstacles we (and probably everyone who does a migration) needed to solve were:

• Changing UPN’s on all the accounts to the users primary smtp address
• Establish ADFS and DirSync
• Changing certificates that were using the current UPN’s and therefor would be rendered invalid.
• Import the ~8000 accounts that only existed in Domino and not in Active Directory and keep them synced.
• Sync the other 10000 accounts that existed in both Domino and Active Directory
• Migrate distribution lists
• Migrate rooms
• Migrate shared mailboxes with their access lists
• Build forms to enable users to do some of the management themselves
• Make sure mail flow works during the “hybrid” period
• Migrating mobile device id’s allowed to sync through Active Sync
• Provisioning of new accounts in Office 365 that work with our current processes
• Automate all the common tasks (creating mailboxes, shared mailboxes, managing distribution lists, approving devices, managing licenses etc.)
• And more… 🙂

Since a lot of people out there are probably doing, or will be doing, the same thing we did, I will try to do a couple of post on how we solved these tasks (at least those related to powershell), share some code and good cmdlets for managing everything from rooms to mobile devices,

Hopefully this will become a good repository for myself and for anyone out there facing the same challenge we did 🙂