Status	Pending Stakeholder Review
Owner	Gautier Todoschini
Stakeholders	John Donovan, Frank Bolata, Boris Foiselle

Issue

Gmail uses a label-based system that supports multiple nested sublabels, while Microsoft 365 relies on a traditional folder hierarchy with different technical constraints.

Recommendation

Adopt the “No Labels” approach for the migration which will not create duplicates. Users should be informed that their Gmail labels will not be preserved.

Background & Context

In microsoft Exchange Mail labels don't exist. But the mails are organized in folders. So the difference of a mail in Google VS Exchange means going from a mail with mulitple labels to a mail in one folder in the future. To migrate a decision needs to be taken how to handle the conversion

Assumptions

- Users will receive guidance and training on the new folder-based structure.
- Users are willing to adapt to changes in mail organization.
- Migration tools will successfully move all messages without data loss.

Constraints

- Outlook’s folder model cannot fully replicate Gmail labels and hierarchy.
- Migration must fit within defined timelines, limiting extensive pre-migration adjustments.
- There is no way in Microsoft FastTrack to limit the number of labels
- There is no way of listing all labels for all mailboxes
- Support and training resources are limited, constraining the speed of user adoption.

Impacts

Users will see changes in how their mail is organized and located after moving from labels to folders.This can cause confusion, slowdown in daily work and increase in support requests.
Mailbox sizes may also increase, creating additional management overhead. Clear communication and guidance will be needed to ease the transition.

Business Rules

Options considered

Option 1 “No labels”
Labels aren’t migrated at all. All mail lands in a simplified folder structure Inbox. Users lose their Gmail organization, but avoid duplication and hierarchy issues.

Option 2 “All labels to folders”
The labels are all converted to Folders/subfolders and the mail is saved in all folder representing all labels. This means every mail will be duplicated by the number of labels attached.

Evaluation

	Option 1: No Labels	Option 2: All Labels to folder
Technical Feasibility	16 K active users (20 K active Mailboxes ~229 TB mailbox + ~181 TB MyDrive) 3194 active shared drives (~ 63,6 TB Shared Drives)+ 2116 AODocs Lib. (13,7 TB)	Can tailor the waves to adhere to the constraints imposed by Microsoft Fastrack
User Impact	All of Syensqo is impacted at the same time "bank aid" approach in some cases can be seen as a better approach to change management	Collaboration between users of the same GBU will be easier as they will not have any coexistence period within Should collaboration need to occur with a GBU/BSA or GBS that has not yet migrated users will need to follow coexistence recommendation
Support Impact	Little possibility to ramp up the IT Support organisation, over the weekend they need to go from supporting fully one tool to another one	Ramp up of full support through a controlled process Will be supporting the users in a same country on two different platforms
Operational Complexity
GBU/BSA/GBS Feedback
Cost