Starting October 2026, Microsoft is retiring Exchange Web Services (EWS) in Exchange Online, and Salesforce features that rely on EWS (Einstein Activity Capture, Salesforce Inbox, and Lightning Sync) must move to Microsoft Graph to avoid sync failures. Salesforce and Microsoft recommend completing the upgrade by August 3, 2026 to avoid disruption — start by identifying your connection type, securing Azure admin consent, testing in a sandbox, then upgrading and monitoring sync health.
EWS has been the backbone of how Salesforce connects to Microsoft Office 365 mailboxes and calendars. Specifically, Salesforce uses EWS to power three critical features that your sales team likely depends on daily. Microsoft is phasing out EWS in favor of Microsoft Graph API, a more modern and secure authentication method.
This retirement isn't happening overnight, but it's important to understand the timeline and act now to avoid service disruption to your Salesforce environment.
One piece of good news: if your organization set up Einstein Activity Capture with Microsoft 365 any time from Spring '26 onward, it already authenticates through Microsoft Graph automatically — no action needed. The upgrade only applies to connections configured before Spring '26 on the older EWS protocol.
If your org uses Microsoft 365 with Salesforce, these are the big three:
EAC automatically captures emails, events, and contacts and associates them to the right Salesforce records. Without a Graph-based connection, that automatic capture can stop, which forces manual logging and lowers CRM data completeness. If your organization relies on sales activity tracking in Salesforce, this is critical to address immediately.
Inbox brings email productivity into Salesforce (send, track, log). Salesforce notes that Inbox orgs configured before Spring '26 may need a manual upgrade to Microsoft Graph, and users must reconnect their Microsoft accounts to complete the transition. For teams using emails like real activities in Salesforce, this tool is essential to your workflow and sales productivity.
Lightning Sync configurations using EWS will stop capturing or syncing data from Microsoft after EWS is retired, and Salesforce recommends planning for Microsoft Graph or moving from Lightning Sync to EAC, depending on your use case.
Think of EWS like an old connector with limited future support. Graph is the new standard interface Microsoft is investing in.
Your upgrade path depends on how authentication is configured today.
In Salesforce Setup, identify:
This audit prevents “silent failure” scenarios, where some teams keep syncing while others drop off.
Before the upgrade can be completed, your organization's Azure admin needs to grant Microsoft Graph consent at the org level. This is a prerequisite step, not something that can be skipped or done later in the process — loop in your Azure admin early so it doesn't become the bottleneck against the August 3 deadline.
Check that your organization holds the required Outlook Microsoft Graph licenses for each feature you use — Outlook Integration, Inbox, and Einstein Activity Capture. Missing licenses are a common cause of stalled upgrades, so confirm this alongside your audit rather than after you've started the technical work.
Before production:
If your org has multiple integrations, treat testing as mandatory, not optional.
If you use Einstein Activity Capture: once Azure consent and licensing are confirmed, complete the authentication upgrade directly from Salesforce Setup under Einstein Activity Capture > Settings, following Salesforce's Graph upgrade guidance for Office 365 authentication method changes.
If you use Salesforce Inbox: Salesforce provides an upgrade flow in Inbox Setup Assistant, and notes users must reconnect after the upgrade.
If you use Lightning Sync: Salesforce advises planning for Graph and evaluating options, including moving from Lightning Sync to EAC where appropriate.
Track:
Set alerts where possible so failures surface fast.
If you don't upgrade before EWS is fully retired, you'll experience significant service disruptions in Salesforce:
In practical terms: fewer logged activities, weaker pipeline hygiene, and forecasting that relies more on rep memory than system evidence.
Does EWS retirement affect on-premises Exchange Server?
Microsoft’s retirement is focused on Exchange Online (Microsoft 365), not necessarily on-prem Exchange Server in the same way. Confirm your environment and plan accordingly.
Which Salesforce tools need Microsoft Graph?
Salesforce calls out Einstein Activity Capture, Salesforce Inbox, and Lightning Sync as impacted features that should upgrade authentication to Microsoft Graph.
What's the recommended deadline to upgrade?
Salesforce and Microsoft recommend completing the upgrade by August 3, 2026, well ahead of the October 2026 retirement, to avoid any disruption to email and calendar sync.
Will users need to reconnect their Microsoft accounts?
For some Inbox configurations, Salesforce states users must reconnect after the admin upgrades to Graph.
When is Microsoft retiring EWS for Exchange Online?
Microsoft’s retirement begins October 2026, with a permanent shutdown in April 2027.
Do I need to upgrade Salesforce Inbox to Microsoft Graph?
Yes, if Inbox is using EWS, you’ll need to upgrade to Microsoft Graph to avoid disruptions. Older configurations may require a manual upgrade, and users will likely need to reconnect their accounts.
How do I upgrade Salesforce EAC from EWS to Microsoft Graph?
Confirm your current authentication method in Setup > Einstein Activity Capture > Settings, then have your Azure admin grant Microsoft Graph consent for the organization. Once consent is in place, complete the upgrade from the same Settings page and reauthorize the integration, following Salesforce's guided update steps. Test in a sandbox to confirm email and calendar capture and monitor sync closely after going live.
If you run a complex Salesforce environment with multiple Microsoft touchpoints, a structured migration plan (audit, test, cutover, monitor) will reduce downtime and protect activity data quality.
Need further assistance? Concept's Salesforce Consulting team is here to help however we can.