Exchange Web Services (EWS) Deprecation and Barracuda Message Archiver

Microsoft is retiring Exchange Web Services (EWS) for Exchange Online, effective October 1, 2026. After this date, Microsoft will begin blocking EWS requests from non-Microsoft applications connecting to Exchange Online. For more details, see Microsoft's article on Deprecation of Exchange Web Services in Exchange Online.

Barracuda Message Archiver (BMA) version 5.5.4 addresses this Microsoft change by transitioning Exchange Online archiving jobs from EWS to Microsoft Graph API.

Note: Customers using Barracuda Message Archiver with on-premises Exchange Server are not affected by this change. EWS will continue to be supported for Exchange Server deployments.

What is changing?

Microsoft EWS retirement

Microsoft is retiring Exchange Web Services (EWS) as the primary method for third-party applications to access Exchange Online data. Key points from Microsoft’s announcement:

Retirement date: October 1, 2026
Impact: EWS requests from non-Microsoft apps to Exchange Online will be blocked
Alternative: Microsoft Graph API is the modern replacement

Barracuda Message Archiver 5.5.4

Version 5.5.4 includes updated integration capabilities to ensure continued functionality with Microsoft 365 / Exchange Online after the EWS retirement:

Transition from EWS to Microsoft Graph APIs for Exchange Online jobs
Updated authentication mechanisms
Retained archiving functionality for all supported mail sources

Who is affected?

Environment	Impact	Action required

Environment	Impact	Action required
Microsoft 365 / Exchange Online	Affected	Upgrade to BMA 5.5.4 before October 1, 2026.
Exchange Server (on-premises)	Not affected	No immediate action is required. However, keeping your BMA firmware current for security and feature updates is recommended.
Hybrid Exchange Online + on-premises	Partially affected	Upgrade to BMA 5.5.4 to continue Exchange Online archiving.

Required actions for Exchange Online customers

Deadline: Complete the upgrade before October 1, 2026.

Review your current configuration – Confirm whether BMA is configured to archive from Microsoft 365 / Exchange Online using Exchange Integration.
Plan an upgrade window – Schedule a maintenance window for the BMA 5.5.4 upgrade before October 1, 2026.
Upgrade to BMA 5.5.4 – Apply the firmware update through the BMA administrator user interface.
Reconfigure Microsoft 365 integration – Update the Azure AD app registration and permissions for Microsoft Graph API access. Follow How to Configure Microsoft Graph API Permissions for Barracuda Message Archiver 5.5.4.
Verify archiving – Confirm email archiving is functioning correctly after the upgrade.

Important dates

Date	Milestone

Date	Milestone
September 3, 2026	BMA 5.5.4 release with Microsoft Graph API support.
September 15, 2026	Recommended target date to upgrade and validate that your BMA continues to work as before.
October 1, 2026	Microsoft begins blocking EWS requests to Exchange Online.

What happens if you do not upgrade? If you use Exchange Online integration and do not upgrade to BMA 5.5.4 before October 1, 2026, email archiving from Microsoft 365 / Exchange Online will stop working. New emails and non-email items will not be archived from Exchange Online mailboxes. Existing archived email remains intact and searchable.

Frequently Asked Questions

Will my existing archived emails be affected?
No. Previously archived emails remain intact and accessible. Only new archiving from Exchange Online is affected if BMA is not upgraded.
Do I need to reconfigure my archiving after the upgrade?
Yes. Customers using Exchange Online integration will need to update their Azure AD app registration to grant Microsoft Graph API permissions. See How to Configure Microsoft Graph API Permissions for Barracuda Message Archiver 5.5.4.
Is there a workaround if I am unable to upgrade before October 1, 2026?
Yes. To keep your Archiver setup running on current firmware until the April 1, 2027 cutoff (the date Microsoft permanently removes EWS access for all tenants), administrators must explicitly enable EWS access via Exchange Online PowerShell and configure the allowed application IDs.
Required steps:
1. Configure the EWSAllowedAppIDs allow list. Validate or configure the EWSAllowedAppIDs setting for your tenant. Microsoft will auto-populate this list in September for tenants that have not configured it, however, administrators are responsible for verifying it is correct for their environment.
2. Enable EWS access by setting EWSEnabled=True for the tenant.
For details, see Introducing EWSAllowedAppIDs: Preparing for the Final Phase of EWS Retirement | Microsoft Community Hub.
Is journaling affected?
SMTP journaling is not affected by the EWS retirement. Exchange Integration archiving that uses EWS requires the BMA 5.5.4 upgrade.
Can I test the upgrade before the deadline?
Yes. Barracuda strongly recommends upgrading and testing before September 15, 2026 to help ensure a smooth transition.

Need help?

If you have questions about this notice or need assistance with the upgrade, contact Barracuda Networks Technical Support.