Microsoft is retiring EWS: what it means for your shared contacts

In October 2026, Microsoft retires Exchange Web Services (EWS) for Exchange Online. This is not a soft deprecation — after the cutoff, EWS requests to Exchange Online stop working. For most users the change is invisible: Outlook and modern integrations moved to Microsoft Graph years ago. But there is one group with a real deadline attached: organizations that keep shared contacts in Public Folders.

If your company has a “Company Contacts” or “Vendors” folder that everyone opens from Outlook’s folder tree, this post is for you. Here is who is affected, why Public Folder contacts have no like-for-like replacement, and a concrete migration plan.

Who is affected

You are in the blast radius if any of the following sounds familiar:

• Your organization maintains one or more contact-type Public Folders in Exchange Online, and people access them through the Outlook folder pane.
• You run third-party tools or scripts that read or write contacts via EWS — sync utilities, CRM connectors, PowerShell automation built on the EWS Managed API.
• You migrated from on-premises Exchange years ago and carried the Public Folder structure along “temporarily.”

The affected surface is bigger than it looks, because Public Folder contacts were the de facto answer to a question Exchange never answered properly: how does a team share an address book? Public Folders were never great at it — no phone sync, clumsy permissions, invisible in mobile Outlook — but they were the built-in option, so they accumulated years of data.

Why there is no drop-in replacement

Microsoft’s guidance for EWS-dependent workloads is to move to Microsoft Graph. The catch: Graph does not expose Public Folders. There is no API to read a Public Folder contact list after EWS is gone, and no Graph-era equivalent of a folder-shared address book.

What Graph does offer is per-mailbox contacts with categories, webhooks for change notifications, and delta queries for efficient sync. That is a good foundation — but it is per-user. Turning it into team-shared contacts requires a layer that manages who shares what with whom, and keeps everyone’s mailboxes in sync. That layer is what Rolyio provides.

The migration plan

Step 1: Inventory what you actually have

Before moving anything, list your contact-type Public Folders and, for each one, answer three questions:

• Who uses it? A folder nobody has opened in two years does not need migrating — it needs archiving.
• Who should be able to edit it? Public Folder permissions were often “everyone can write.” Migration is your chance to introduce real roles.
• How clean is the data? Expect duplicates and dead entries. Budget an hour for cleanup; it pays off permanently.

Step 2: Export each folder to CSV

From Outlook desktop, use File → Open & Export → Import/Export → Export to a file (CSV) with the Public Folder selected as the source. Do this per folder — a folder maps naturally to one shared label later. While the data is in a spreadsheet, deduplicate by email address and delete stale entries.

Step 3: Choose an owner for each list

In the Public Folder model, contact lists were institutionally owned and individually neglected. In the label model, each list has an explicit owner — typically the person or role who actually maintains the data (office manager for company-wide contacts, sales ops for customers). Ownership is transferable later, so this is not a permanent commitment; when an owner hands off a label, they stay on as an Edit collaborator.

Step 4: Import into a label and share it

In Rolyio, the owner connects their Microsoft account, creates a label per folder (labels on the Microsoft side are real Outlook categories), and imports the cleaned CSV into the open label. Then they share the label:

• with specific people by email,
• with a distribution/domain group (expanded into its members),
• or with the entire domain — which, unlike a Public Folder permission set, automatically includes future accounts, so new employees get the list on day one.

Each recipient chooses nothing and installs nothing extra: after sync, a “Company Contacts (Shared)” category appears in their own mailbox. Assign View to most people and Edit to maintainers — see roles and permissions for the details.

Step 5: Run both in parallel, then retire the folder

Keep the Public Folder read-only for a transition period (two to four weeks) while people confirm the shared label has everything. Then remove the folder. Do not skip the read-only step — the fastest way to lose data is two writable sources of truth.

What you gain over Public Folders

This migration is forced, but the destination is better than the origin:

• Phone sync. Public Folder contacts never reached mobile address books. Shared labels are native Outlook categories in each user’s own mailbox, so they show up on phones and in mobile Outlook search.
• Near-real-time updates. Rolyio subscribes to Microsoft Graph webhooks, so a change made by the list owner reaches recipients in near real time — no folder cache refresh delays.
• Real roles. View, Edit, and Can reshare replace the blunt folder ACLs.
• Revocation. Removing someone’s access removes the contacts from their mailbox on the next sync — something a copied or exported folder never allowed.
• A safety net. Deleted shared contacts keep a snapshot in Trash for 30 days, so a botched cleanup is reversible.

One architectural point worth knowing: your contacts stay in Microsoft 365. Rolyio stores the sharing relationships and permissions, not a copy of your address book — so migrating to it is not trading one data silo for another.

Timing

October 2026 sounds distant until you subtract a parallel-run period, a cleanup pass, and the usual quarter of organizational latency. Teams that migrate in the next few months do it calmly; teams that start in September will do it in a hurry. The export-import-share loop for a single folder takes under an hour — start with your most-used one and see.