Leaving Microsoft 365 without your team noticing on Monday

When a company considers leaving Microsoft 365, the first thing people think of is email. But email is rarely the problem. The hard part is the habits and connections that have grown over the years. Map those out first and you can switch without colleagues getting stuck on Monday morning.

What really ties you to Microsoft

Go through this list and note how much each item matters for you:

• Outlook habits. People are used to a folder list on the left, a reading pane and a calendar in the same program. That is a habit, not a technical dependency. Any mail program with the same layout takes care of most of it.
• Shared mailboxes. info@, invoices@, support@. These matter, because that is where work comes in. Put them on a separate list.
• OneDrive and SharePoint. Files are easy to copy. The harder part is the permissions per folder and the links people have pasted into emails and documents.
• Teams. Meetings are quickly replaced. Chat history is the tricky part, more on that below.
• Excel with heavy macros. This is often where real business logic lives, and it does not always behave the same in another program.
• Signing in to other apps with Microsoft. Many companies use Entra ID to sign in to accounting, CRM or HR software. When that account disappears, nobody can get in. This is the item people forget most often.

In practice the last two weigh the most. The rest is mostly planning.

What about the EU Data Boundary?

With the EU Data Boundary, Microsoft has committed to storing and processing the data of European customers within the EU. That is a genuine improvement. It does not change who owns the company, though: Microsoft remains an American company and falls under the US Cloud Act. The US government can still require Microsoft to hand over data, even when that data is stored in Europe. For the legal background, read our article on transfers outside the EEA.

An order that works

1. Take inventory. Who has which mailbox, which shared mailboxes exist, which apps use Microsoft sign-in, and which Excel files have macros that must not break.
2. Check your licences. See when your subscription ends and whether it runs monthly or yearly. Keep the licences until the move is complete, so you can still look things up in the old mailboxes for a few weeks.
3. Sort out sign-in for other apps first. Give every app that uses Entra ID its own account or another sign-in method before you switch anything off.
4. Decide what happens to each shared mailbox. Does it become a mailbox of its own, a forward, or can it go? Agree who looks after it.
5. Move mail, calendars and contacts. Lower the TTL of your DNS records a few days in advance. Switch the MX record on Friday afternoon, move over the weekend, and have everyone sign in to the new environment on Monday.
6. Copy the files. Bring over the folder structure and the permissions, and tell colleagues that old OneDrive links will stop working.
7. Leave the Teams chats behind. Chat history is usually not migrated. Export what you need to keep and agree on a start date for the new chat.

Desktop Office can stay installed if you need it. Word and Excel open files from any storage.

What you can keep from Microsoft

You do not have to give up everything at once. If the finance team has an Excel model with macros that nobody dares to touch, keep a separate Office licence for those few people. Microsoft also simply does some things well: several people editing at the same time in desktop Word, Power BI for reporting, and Dynamics if your business processes run on it. If those are truly essential, a mixed setup is fine. The goal is that your everyday mail, files and conversations no longer sit with an American supplier.

Where Binadit fits

Binadit Workspace covers the everyday part: mail with calendar and contacts on your own domain, Drive, Office in the browser on ordinary .docx and .xlsx files, Meet and the Conserio chat. Everything runs on servers in the Netherlands, from a Dutch company, so the Cloud Act does not apply. The full overview is on the page about an alternative to Microsoft 365, and there is a separate page on replacing Teams.

The Binadit Workspace Migration app moves mail, calendars and contacts out of Microsoft 365, account by account. It does not move files from OneDrive and SharePoint; we help you copy those. For people who are attached to Outlook there is Northmail: a free mail program laid out like classic Outlook, for macOS, Windows, Linux, iPhone and iPad. More on the Outlook alternative page. That way Monday morning looks mostly the same.