MS Deprecating EWS API

[RyanJ]

There was a recent announcement that MS is deprecating the EWS API and recommending that people switch entirely to Graph API. I know VBO365 uses Graph API already for some things, but still uses EWS for Exchange backups. It seems they recently updated the bulletin to specify exactly which APIs are being decommissioned, so I'm not exactly clear on what this means from a backup perspective.

Bulletin: https://techcommunity.microsoft.com/t5/ ... -p/2813925

"We will also remove the ability to register new apps in Azure with EWS permissions starting September 30, 2022"
"We strongly urge our ecosystem partners accessing Exchange Online data to migrate to Microsoft Graph APIs."

The issue I'm seeing is, Graph APIs don't provide full fidelity messages the same way EWS does yet.

How will this change by MS affect VBO backups?

[Mike Resseler]

Not at this moment. We are aware of which ones are getting deprecated and continue to change EWS API's for GRAPH API's if they become available. MSFT works with us on this and tries to get as much Graph API's available as fast as possible

[RyanJ]

Good to know, I assumed Veeam would be fully aware, but I just wanted to have some more info when I get asked about it.

Thanks!

[DM-JM]

Any update on this? EWS is set to be retired October 1, 2026 so not an immediate issue. But the VBM365 User Guide for 7.0 still has EWS APIs EWS.AccessAsUser.All and full_access_as_app listed as requirements.

[Mildur]

Hello Jason

Our teams have already started their planning. We will provide necessary product updates before Microsoft retires the EWS API in October 2026.

Best,
Fabian

[ethanfang]

Hello,
It's closer to October 2026. MS is gonna deprecate the EWS API and recommend all solutions to entirely use Graph API. VBO365 uses Graph API already for some cases, but still uses EWS for Exchange backups. Will this affect the backup when it's October 2026?
Best regards,
Ethan Fang

[Mildur]

Hi Ethan

We still have 16 months to rebuild our Exchange Online backup integration.
The current version still requires EWS, but we will provide an update before October 2026 so you can continue your backups when EWS API is deprecated.

Best,
Fabian

[ethanfang]

Hi，Mildur
I wanna backup in place archive mailbox with Veeam, will this still work when EWS API is deprecated? Since I've found it stated here as below that graph api doesn't support in-place archive mailbox. So if ews api is deprecated, is there still a way to backup in-place archive mailboxes?
The API does not support accessing in-place archive mailboxes, not on Exchange Online nor on Exchange Server.
https://learn.microsoft.com/en-us/graph ... h-rest-1.0
Thank you~!
Best regards,
Ethan Fang

[Mildur]

Hi Ethan,

Our goal is to provide the same workload support as before.
While some API functionality may be missing today, we are able to discuss and request additional APIs from Microsoft for exporting and restoring customer data from Microsoft 365.

I suggest checking back in about a year, when we’ll have more clarity on the implementation details and which functions may remain limited due to missing or unsupported API endpoints.

Best,
Fabian

[ethanfang]

Hi，Fabian
Sounds great, in this case I think we can keep using Veeam for backing up microsoft. So you're currently coworking in progress with Microsoft to push them to add new graph api to backup in-place archive mailbox right?
That's really a good news to know, because Microsoft doesn't release any news or update on graph api capability, so we're really worried that veeam will stop supporting backup in-place archive mailbox~!
Thank you,
Best regards,
Ethan Fang

[Mildur]

Hi Ethan,

Yes, we are able to discuss requests directly with Microsoft.

Just to clarify, other backup vendors will face the same challenge when EWS is deprecated — they’ll also need to switch to Graph API and will encounter the same limitations as we do.

Best,
Fabian

[kevin__]

Hi Fabian,

Following up on the previous discussion, I also have a specific need to back up in-place archive mailboxes, so I’m especially interested in any updates regarding how Veeam will handle the upcoming EWS retirement.

Just checking if there’s any new information:

1. Does Veeam have a plan for this change? Any idea how it will be addressed?
2. For backups created before EWS is retired, will the existing backup data format still be usable after EWS is officially retired? If not, will we need to re-backup everything?
3. Microsoft’s announcement (link) mentions Access to Archive Mailboxes as part of the EWS retirement. Will Veeam rely on Graph API to handle archive mailboxes, or another approach?

Thanks for any updates or insights!

Best,
Kevin

[Polina]

Hi Kevin,

1) We're planning to fully switch to Graph APIs, and we already know that those have some limitations compared to what could be achieved when using EWS.
2) I expect to keep existing backups usable for restores. The scope of limitations yet to be defined.
3) To be be investigated/desided.

Thanks!

[DaStivi]

Microsoft is sending out admin center messages to affected customers:

[Polina]

Hi Stephan,

We're aware of the upcoming changes and RND is currently working on the corresponding changes in the solution.

Thanks!

[MPlesnerJ]

Hi all, I just want to point out that Veeam Data Cloud now has a backup mode, "Express backup policies," that uses the "Microsoft 365 Backup Storage" back-end. This can be a temporary fix to guarantee the protection of users' mailboxes using Veeam Cloud Baas solution. It is sold on a per-user user level. But it is cloud and not a Veeam Backup for Microsoft 365 solution, as we know in this part of the forum.

[FAlter]

Microsoft is sending out admin center messages to affected customers:

We got a very similiar notification today:

Action Required: Update active Exchange Web Services Applications
In 2018, we announced that we were no longer making feature updates to Exchange Web Services (EWS) in Exchange Online, and we advised developers to move to Microsoft Graph.

In September 2023, we announced that on October 1, 2026, we will start blocking EWS requests to Exchange Online.

We are now less than 12 months from October 1, 2026. We have made progress on closing most parity gaps with more changes in development to be released in the coming quarters. Please refer to Deprecation of Exchange Web Services in Exchange Online for up-to-date guidance and roadmap information.

You are receiving this notification because there are EWS applications in your tenant.

If you haven't already, start the process of working with your application development organization and your application vendors to either sunset or migrate active EWS applications on your tenant to the Graph API, Power Platform, or Copilot Declarative Agents.

The vast majority of custom EWS applications can be safely migrated to alternative technologies today.

When this will happen:

October 1, 2026

How this affects your organization:

In October 2026 we will begin disabling EWS on all M365 tenants worldwide. EWS Applications that have not been migrated will stop functioning.

The following applications on your tenant use EWS:

Entra Application ID

... here a GUID which in Entra is named "Veeam Backup with Modern Authentication"...

Next Steps

1. Review your application portfolio now to get an understanding of which apps need to be updated by your organization and which ones require updates from vendors.
2. While EWS applications are active on your tenant, lower your risk of a successful attack by reviewing and updating the security practices for your organization. In particular, enable Multi Factor Authentication (MFA) for all users including test accounts.
3. Prioritize EWS app modernization on your engineering schedule to ensure enough time to address any functionality gaps
4. Disable EWS in your tenant or enable Baseline Security Mode when you no longer have applications that depend on it.

Note on Apple Mail for Mac

Apple Mail for Mac and related applications are some of the most popular EWS applications. We are working closely with Apple to update these applications. In order to run your tenant in the most secure configuration today, users of Apple Mail for Mac would have to switch to an alternative like Outlook for Mac until the applications have been updated.
We provide a set of open-source tools and tutorials to aid in discovery, analysis and AI assisted modernization of EWS applications.

Thank you in advance for taking steps to improve the security posture of your M365 tenant. We are extremely excited about the growing opportunities that the Microsoft 365 platform offers to developers, and we remain fully committed to our journey to empower developers with the best features and tools.

The deadline seems quite clearly 1st October 2026.

@Ploina: Good to hear - how is the schedule?

[Polina]

@FAlter

Kindly see above.