M365 Migration FAQs

M365 Migration FAQ
As we continue our transition to Composition Brands and establish our own technology environment, we will be moving several IT services away from Middleby and into the new Composition Brands environment.

A key part of this transition is the migration of Microsoft 365, including services such as Outlook, Teams, OneDrive, and other Microsoft applications used as part of our day-to-day work.

We recognise that changes of this nature can sometimes be disruptive, so we have created this resource centre to help make the transition as straightforward as possible. Here you will find practical guides and instructions covering the key steps you may need to complete before, during and after your Microsoft 365 migration.

Please use the guides below to support you through the process. If you experience any problems or require additional assistance, the IT team will be available to help throughout the migration.

General Migration Experience
Will I lose access to my emails or files after migration? +
All emails and O365 files should be present once the migration has completed, if you are missing any emails or, files please report this to your local IT team
Will my mailbox size or existing data be affected? +
Migration does not delete or alter existing data in your source or destination mailbox. Items already present remain unchanged.
Which applications/services are in scope and how are they handled? +
• Office Suite (web) – Content Migrated and licensing reassigned
• Office Suite (desktop) – Content Migrated with Evergreen, licensing reassigned.
• Power Suite (web) {Power BI, PowerApps, Power Automate} Content NOT migrated, licensing reassigned.
• Power Suite (Desktop) {Power BI, PowerApps, Power Automate} Content NOT migrated, licensing reassigned.
• MS Planner – Content Migrated (Plans attached to MS Teams ONLY), licensing reassigned.
• Copilot – Content NOT migrated, licensing reassigned
• Visual Studio – Content NOT migrated, licensing reassigned.
Will I have a new email address? +
Yes, everyone migrating will have a new email address, however your current address will remain valid for a period of time too. Please refer to direct communication confirming what your email address will be.
Will I need to use a different username to log in? +
The changes will only affect your Office 365 account; you will use your new email address to log into O365. There are no planned changes to how you login to your computer at this time.
What day and time will I be migrated? +
This will be communicated directly to you via email in advance.
How long will migration take? +
Migration will start on a Friday evening; it is expected to be completed for the following Monday morning.
Do I need to backup my files? +
Your OneDrive files are already backed up, these will be migrated for you. If you have files within Planner, Power BI, PowerApps, or Power Automate these will need to be backed up, please refer to the relevant process guides; ‘Microsoft Planner Plan Export to Excel Procedure’ & ‘Power BI Power Platform and Power Apps Migration Procedure’
Will shared mailboxes still work?+
Your access to shared mailboxes should still be present, with the web first approach immediately post migration you may need to add shared mailboxes to your view. Please see the ‘Adding a shared mailbox’ guide for steps to follow.
Will Outlook need to be reconfigured?+
Yes, Outlook will need to be reconfigured, please look out for notifications in advance of and post migration (via Outlook web) on steps to be taken.
Will my Team meeting links still work?+
Existing Teams meeting links will no longer work after migration, especially recurring meetings. If you organize important recurring meetings, recreate them in the new tenant and send updated invites after migration.
What happens to files I have shared with others?+
People who previously had access to files or folders you shared will lose access. You will need to reshare important OneDrive files or folders from the new tenant.
What Gets Migrated and What Doesn’t
After migration, my Power Platform content didn’t migrate. What can I do to resolve the issue?+
Power Platform content does not automatically migrate to the new Composition Brands tenant. To export and re-import your content, follow the Power Platform Migration Procedure.
Will my bookmarks\favourites move during migration?+
Browser bookmarks\favourites do not migrate during an M365 migration. If you wish to retain your bookmarks for use after migration, please follow the Microsoft Edge Bookmark Export & Import Procedure.
Will my MS Planner plans be migrated during the migration?+
Planner plans will migrate if the plans are connected to a Microsoft Team or Teams-based group. Plans not connected to Microsoft Teams will not be migrated.
Which items will migrate successfully?+
Most standard mailbox items (emails, folders, attachments) migrate. Hidden system folders and encrypted content migrate in their original state (certificates may be needed to view). Colour categories and folder structures are preserved.
What will NOT migrate?+
• Private chats and Teams chat history with external users.
• Personal distribution lists (contact groups)
• Folder calendar notifications, modified description text, modified attendee lists for exceptions, attendance status for attendees.
• Mailbox sharing settings (aliases, client settings, delegates like SendAS/SendOnBehalf)
• OneDrive shared links (you must re-share after migration)
• Client-side rules
• Delegated permissions or custom folder permissions may require manual reapplication.
• Items that do not match folder types (e.g. calendar responses inside a mail folder)
Will my contacts be migrated?+
All contacts should be present once the migration has completed, if you are missing any contacts, please report this to your local IT team.
Post-Migration Changes
Why do I see duplicate chats or missing conversations in Teams?+
Tenant-to-tenant migrations create new chats for migrated identities. Old chats remain in the source tenant but will not sync after migration.
Will my calendar and contacts migrate?+
Yes but after migration verify automatic replies and calendar permissions are applied correctly.
Why are some of my Power BI reports no longer pulling data from data centre sources?+
During the migration, PBI gateway services were modified to redirect your reports to their data centre sources via your new account. This modification changes the on-prem gateway location. It may take up to 72 hours before reports redirect to their sources after logging into the Power BI service with your new account. If you experience issues with your reports beyond the 72 hour period, please reach out to your local IT team for assistance.
Common Migration Issues & Solutions
Outlook Classic does not allow me to login with my account after migration.+
This is usually caused by Autodiscover settings or stored tokens. To resolve it, follow the Recreate Outlook Classic Profile Procedure.
What do I do if I encounter missing files or emails?+
Contact your local IT Support team if you believe files or emails are missing.
Why is my account locked after trying to sign in at https://www.office.com?+
Multiple unsuccessful attempts trigger account lockout. Contact your local IT team to reset the temporary password and unlock the account.
How do I add a guest user or member to a Team?+
To add a guest user or member to a Team, please follow the Teams How to add a Guest User or Member guide.
How do I switch between Teams on different Tenants?+
If you have been given access to Teams across two different tenants, you will need to switch between them. Under your account, choose the other tenant. Detailed instructions are provided in the Accessing Teams Across Tenants procedure.
Common Mobile Device Issues
When I try to access M365 applications from my mobile device, it isn’t working. How can I fix the issue?+
This is usually caused by mobile credential caching and/or device registration issues. To resolve it, follow the M365 Mobile Device Post-Migration Recovery Procedure.
After migration, I cannot reconnect my mobile derive to the new tenant.+
Sign out of all Microsoft apps on the device, remove the old “Middleby” account from Microsoft Authenticator, then add in the new Composition Brands M365 account. If instructed to run Evergreen, remove the old account in Authenticator before running Evergreen on your computer.
Common Evergreen Issues
After running Evergreen, I get a blank white screen when signing into Office apps.+
This can happen if the account is not activated first. Go to https://www.office.com and sign in with your migrated account before signing in to locally installed office apps.
Evergreen shows : “CurrentUser policy is Undefined… Effective execution policy is RemoteSigned… unsupported for Evergreen.”+
The local execution policy did not update. Contact your local IT support team to re-run the execution policy update script.
Why does Chrome keep taking me back to my old account?+
Chrome is not updated by Evergreen. When in Chrome, press Ctrl+Shift+Del, chose “Show More,” check all options, and delete browsing data to clear the old session.
User Support After Migration
Where can I find help post-migration?+
Submit issues to your local IT support team as normal.