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 Option 1 “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	Easy to implement and easy to revert.	Duplication of the mails will endanger the mailbox limits. More difficult to revert due to duplicates & hierarchy
User Impact	All mails will be in inbox and need to be restructured again in the new folder strcuture Users can be educated to use rules to automate as much as possible.	The label structure will be recreated in folders and mails will be duplicated. So searching for a mail will give multiple results.
Operational Complexity	Simple migration	Limits will be hit earlier because of mail duplication - 124 mailboxes concerned
GBU/BSA/GBS Feedback
Cost	Lower Cost	High cost due to cleanup