Microsoft 365 Contact Management: Differences across Desktop & Web Outlook

Here’s a video walkthrough from Tom (Contactzilla founder) explaining what’s really going on with shared contacts in Microsoft 365. It’s a great visual companion to the guide below, especially if you want to see the quirks in action.

One of the things we hear most often from teams is:

“Can we push contacts to Outlook and have them grouped by category?”

If you have hundreds or thousands of contacts, there’s all sorts of reasons you might want to split them into groups like Clients, Crew, VIPs, region based groups etc.

But Outlook behaves differently depending on how you access it. The desktop app and the web version have different rules when it comes to contacts and how you can categorize them. Even within the web version, a toggle labelled ‘New Contacts’ (meaning you switch to their updated UI) completely changes how categories and folders work.

Here’s what’s actually going on and why it’s harder than it should be to get consistent behaviour.

How Microsoft 365 Manages Contacts Differently on Outlook Desktop vs Web

Back in 2022, Microsoft announced a redesigned contacts experience for Outlook on the web, promising simpler syncing, cleaner categorisation, and better consistency across devices. You can read their original blog post here. It was a big step in the right direction. But as we’ll see, things still behave quite differently depending on how you access Outlook.

Outlook contacts can be accessed in two main ways: via the desktop app, or through a browser in Outlook on the web. And while they’re both part of Microsoft 365, they don’t behave the same, especially when it comes to folders and categories.

Outlook Desktop shows what Microsoft calls the New Contacts experience. Meanwhile, Outlook on the web still defaults to the older Classic Contacts layout unless you manually switch it using the toggle in the top-right corner. Many organisations we speak to much prefer the classic view, either out of preference or because the new interface isn’t compatible with other tools they rely on.

Tip 💡: For IOS Users – If you’ve enabled Outlook’s Save Contacts feature and see duplicates in Apple’s Contacts app, it’s a known sync issue. See Microsoft’s guide on resolving these: Duplicate Outlook contacts appear in iOS Contacts app

Folders vs Categories

Microsoft has updated Outlook’s contact system to move away from folders and toward categories. In their own words, categories are ‘a new, easy, modern way of managing contacts,‘ designed to replace folders with tag-style grouping.

In Outlook on the web folders are still visible but In Outlook Desktop, folders have been removed entirely. You now group contacts using categories only.

If you create a new category in Outlook Desktop, it doesn’t show up in Outlook on the web neither as a category nor a folder. Microsoft have stated this themselves in the blo: *Known limitation: Folders on Outlook desktop will show as categories in Outlook on the web. New categories created or contacts stamped newly with categories on Outlook on the web will not reflect on Outlook desktop as corresponding folders.

If you have been using folders in Outlook Web and toggle to New Contacts mode your folders will simply vanish from view.

You can still assign a contact to a category, but the option to move it to a folder disappears.

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How Contact Folders Behave Behind the Scenes

Even though folders have been phased out in the new contact model, they still exist in the background and can still be created via Microsoft’s Graph API.

These folders won’t always be visible in the UI, depending on the version of Outlook you’re using. But that doesn’t mean they’re gone. They can still contain contacts and affect how data is structured behind the scenes.

So it’s possible to end up with folders that technically exist, and even have contacts in them, but are invisible depending on how you access Outlook.

The ‘Directories’ View in Outlook Web

Another key difference between the two versions is the ‘Directories’ panel, which is only available in Outlook Web. It includes directories like All Users, All Contacts, Distribution Lists, Offline Global Address List, and Public Folders.

The naming here is misleading. The All Contacts section sounds like it should contain every contact in your organisation, but in fact it only includes contacts that have been added globally via the Microsoft 365 admin console.

So if you do want to add any contacts to the global address list you need to have admin privileges and you can only do it by logging into the 365 admin console which is yet again another UI entirely. The Offline Global Address List seems to be an amalgamation of the All users and All Contacts directories, but it doesn’t include your personal or shared contacts. And Public Folders, while shown, aren’t editable. There’s no clear way to add to them, and no real documentation on how they’re intended to be used for contact sharing.

Outlook Desktop doesn’t show the directories view at all. So if you’re expecting to manage or even just see those shared global contacts from the desktop app, you’ll be out of luck.

Global vs Personal Contacts

While Outlook’s Directories include centrally managed contacts like All Contacts and All Users, these are part of your organisation’s global address list. You can’t edit them directly from the Outlook interface, and Microsoft doesn’t currently offer an API to manage them.

Your personal Contacts folder, on the other hand, is editable. This is the list you see in the left-hand pane of Outlook Desktop or Web (outside of the Directories section). It’s where new contacts are created by default, and it’s where categories can be applied.

What the Graph API Can and Can’t Do

From a developer’s perspective, managing contacts via Microsoft’s Graph API is limited in several key ways.

You can use the API to create and update personal contacts (the ones that live in a user’s personal contacts folder). You can also create folders. As we have discussed though these will only appear in Outlook Web when using the Classic view.

But there are key limitations:

No access to the Global Address List (GAL): There’s no way to create or manage contacts in the ‘All Contacts’ directory through the API. That area can only be updated from the Microsoft 365 admin console, by someone with admin permissions.
Orphaned categories: These occur when a category is removed from the master category list, but is still attached to a contact. Outlook no longer recognises it as a valid label. It can’t be reassigned, and won’t appear in your category picker. But it still lingers in the UI, with no supported way to clean it up via the API. There’s no warning, no error, and no clear way to tell it’s orphaned, just a label that’s stuck in limbo.
No global categories: Categories are stored per mailbox, so there’s no built-in way to create or assign categories that are shared across an entire organisation, despite how useful that would be for organizations to manage global categories.

For anyone building integrations or just trying to keep contact data clean it adds unnecessary complexity.

A Simpler Way to Sync Outlook Contacts

Until now, the only supported way to sync Contactzilla address books with Outlook has been by using a third-party plugin like Outlook CalDAV Synchronizer.

Contactzilla now has a solution for syncing contacts to Outlook that handles some of these complexities and it’s ideal for organizations of any size

You can manage your contact lists centrally in Contactzilla, include categories and push them directly into your team’s Outlook accounts. No plugins. No third-party sync tools. Just a clean, up-to-date contact list that behaves the same across every user’s Outlook. On web, desktop or mobile.

Starting in April 2026, Microsoft has announced that users with Microsoft 365 for Enterprise licenses will be automatically toggled from the classic Outlook for Windows to the new Outlook experience. Users will still have the option to switch back, but this marks a clear signal of where Outlook is headed.

Frequently Asked Questions

Can I turn off the new Outlook Contacts experience for my organization?

Yes. Admins can disable the new Outlook app—or hide the “Try the new Outlook” toggle—by using Exchange Online PowerShell (e.g., Set‑CASMailbox -OneWinNativeOutlookEnabled $false) or deploying Group Policy/Intune policies

What does “All Contacts” mean in Microsoft 365?

“All Contacts” in Outlook Web refers to shared contacts manually created by admins through the Microsoft 365 or Exchange Admin Center—not everyone’s personal or synced contacts. It’s a separate, admin-managed address book that doesn’t include contact folders, categories, or personal address lists.

Why don’t contact categories sync between Outlook Web and Desktop?

Categories created in the desktop version aren’t reflected in the Outlook web. Microsoft explicitly highlights this limitation: ‘Known limitation: Folders on Outlook desktop will show as categories in Outlook on the web. New categories created or contacts stamped newly with categories on Outlook on the web will not reflect on Outlook desktop as corresponding folders.’