Salesforce for Outlook Retires Dec 2027: The Complete Migration Guide

Salesforce for Outlook Retires Dec 2027: The Complete Migration Guide

Salesforce for Outlook (SFO) — the COM desktop add-in that has connected Salesforce and Microsoft Outlook for over a decade — is retiring in December 2027. The product has been in maintenance-only mode since June 2019, the "New Record" action menu broke in the Summer '21 release, and now there's a hard stop on the horizon.

If your org still relies on SFO to sync contacts, events, and tasks between Exchange and Salesforce, you need two separate replacements: the Outlook Integration add-in for the side panel UI, and Einstein Activity Capture (EAC) for contact and calendar sync. This is not a single-product swap. It's two parallel workstreams, and getting either wrong introduces duplicate records or gaps in activity history.

This guide covers the complete SFO migration path: why it's retiring, what breaks when you move to the replacement products, the hidden architectural limitations of EAC, and the technical blueprint for executing the transition without data loss.

Why Salesforce for Outlook Is Retiring

The retirement comes down to a dead technology dependency. SFO is a Component Object Model (COM) desktop add-in that relies on the Internet Explorer 11 embedded browser control to render the Salesforce side panel and process backend API calls. Microsoft ended extended support for IE11 on June 15, 2022. Without a supported browser engine, Salesforce cannot maintain a secure integration, patch vulnerabilities, or push updates.

Rather than rebuild a COM add-in from scratch, Salesforce is consolidating customers onto its modern, web-based products: the Outlook Integration add-in and Einstein Activity Capture.

The timeline has already been stretched once — the original retirement target was June 2024, but Salesforce extended it to December 2027 to give organizations more runway. That extension is now fixed. There is no indication of another delay.

Here's what has already happened:

• June 2019: SFO transitioned to maintenance-only mode. No new features, no new user sign-ups.
• Summer 2021: The "New Record" button in the side panel stopped functioning.
• June 2022: Microsoft ended extended IE11 support, removing the underlying browser engine SFO depends on.
• December 2027: Full product retirement. All sync, side panel, and configuration access ends.

After the deadline, sync stops entirely, the Salesforce side panel in Outlook disappears, and admins lose access to all SFO configurations. Users will be unable to download SFO or view their settings in Salesforce. Unresolved items will no longer process from this tool.

Organizations with 200+ Outlook users should expect the migration to require 8–12 weeks of planning, testing, and execution.

The Two-Part Replacement: Outlook Integration vs. Einstein Activity Capture

SFO did two jobs in one product: it provided a side panel UI for viewing and creating Salesforce records from Outlook, and it provided automated sync of contacts, events, and tasks between Salesforce and Exchange. Salesforce is splitting those into two separate products.

Capability	SFO (Retiring)	Outlook Integration	Einstein Activity Capture
Side panel to view SF records	✅	✅	❌
Create records from Outlook	✅ (broken Summer '21)	✅	❌
Log emails manually	✅	✅	❌ (auto-captures)
Contact sync	✅	❌	✅
Event/calendar sync	✅	❌	✅
Task sync	✅	❌	❌
Custom object sync	✅	❌	❌
Works on Mac / Outlook Web	❌	✅	✅

Outlook Integration (The UI Replacement)

Outlook Integration is a modern, web-based add-in built on the Office.js API. It replaces the SFO side panel and handles all manual email and event logging. Unlike SFO, which was strictly limited to Windows desktop environments, Outlook Integration is platform-agnostic — it works natively in Outlook for Windows, Outlook for Mac, and Outlook on the web (OWA).

Because it doesn't rely on local COM registry keys or legacy browser controls, it's significantly more stable and easier for IT to deploy centrally via the Microsoft 365 Admin Center. Email application publisher layouts originally created for SFO can be reused with Outlook Integration without rebuilding them from scratch.

Einstein Activity Capture (The Sync Replacement)

Einstein Activity Capture replaces the automated background sync of contacts and calendar events. EAC is a server-to-server sync engine that connects Salesforce directly to Microsoft 365 via OAuth 2.0 or Microsoft Graph — no desktop client required.

EAC is not a full feature-for-feature replacement. Two major SFO capabilities have no native equivalent in the modern stack:

1. Task sync. Salesforce's official documentation explicitly states that EAC and Outlook Integration do not sync tasks. The bidirectional task sync SFO provided between Outlook Tasks and Salesforce Activity objects is gone. If your workflows depend on it, you need a custom workaround (see Phase 5 below for a concrete Flow-based approach).

2. Custom object sync. SFO allowed administrators to map synced emails and events to custom objects — relating an email to a custom Project__c or Implementation_Ticket__c record directly from the side panel. EAC is limited to standard objects: Accounts, Contacts, Leads, Opportunities, Cases, Quotes, and Contracts.

For deep coverage of the EAC backend — sync models, Microsoft Graph migration, and the data storage architecture — see our companion guide: Lightning Sync to Einstein Activity Capture: The 2026 Migration Guide.

What Breaks: The Hidden Limitations of Einstein Activity Capture

Salesforce positions EAC as the default upgrade path, but it is not a 1:1 replacement for SFO. If you enable EAC without understanding its architecture, you will break reporting workflows and potentially lose data.

Email Data Storage: AWS, Not Salesforce

When SFO logged an email, it created a physical Task record directly in the Salesforce database — queryable via SOQL, triggerable by Flows, and reportable like any other standard object.

EAC works differently. By default, captured emails are stored off-platform on AWS, not as standard Salesforce objects. Specifically, EAC writes captured emails to an external data store managed by Salesforce infrastructure, then surfaces them on the Activity Timeline via an API call at render time. The emails appear on the record but do not exist as EmailMessage or Task objects in your org's database.

This introduces four severe operational limitations:

• No standard reporting. You cannot query AWS-stored emails via SOQL. You cannot build standard Salesforce reports or dashboards on captured email data. You're limited to the EAC "Activities Dashboard," which is a separate, non-customizable interface.
• No automation. Because no physical record is created on the Salesforce platform, captured emails cannot trigger Flows or Apex triggers. Any automation that fired on Task or EmailMessage insert stops working.
• Data retention limits. On EAC Standard (the free tier), captured email data is permanently deleted after 6 months. On paid tiers, retention extends to 24 months. If a sales cycle lasts 9 months and you're on Standard, the initial correspondence simply disappears from the Activity Timeline with no recovery path.
• No custom fields. You cannot add custom fields to EAC email records stored in AWS.

The Summer '25 release introduced "Sync Email as Salesforce Activity," which writes newly captured emails as native EmailMessage records directly into the Salesforce database. This makes new email data queryable via SOQL, accessible to Flow automations on EmailMessage insert, and reportable in standard Salesforce reports — replacing the AWS-stored activity stub with a real platform object. But the migration is irreversible once enabled, and historical backfill is capped at 180 days. Anything captured before enabling this option stays in AWS and cannot be retroactively converted.

EAC Standard Edition Constraints

EAC Standard is included with Sales Cloud Starter, Professional, Enterprise, and Unlimited editions at no extra charge. But it comes with hard limits: a 100-user cap and 6-month data retention. After 6 months, captured data is permanently and irrecoverably deleted.

The full version — which extends retention to 24 months and removes the user cap — requires Unlimited or Performance editions, or the Sales Cloud Einstein add-on (approximately $50/user/month as of early 2025; verify current pricing with your Salesforce AE).

For organizations with 200+ Outlook users migrating from SFO, the Standard edition's 100-user cap is an immediate blocker that forces a licensing conversation before any technical work begins.

EAC's Contact Matching and Deduplication Logic

The most common failure mode in SFO-to-EAC migrations is duplicate contact and event records, and it happens because EAC's matching logic differs significantly from SFO's.

EAC matches contacts primarily on email address. When EAC syncs a contact from Outlook, it checks whether a Contact or Lead in Salesforce shares the same primary email address. If a match exists, EAC links the sync to that record. If no match exists — or if the email address in Outlook differs from what's stored in Salesforce (even by a subdomain or alias) — EAC creates a new record.

Common failure scenarios:

• Multiple contacts with the same email. EAC's behavior is undefined when multiple Salesforce contacts share an email address. In practice, it links to the most recently modified record, which may not be the correct one.
• Contacts with no email address. Records synced by SFO that lacked an email field will not be matched by EAC and may duplicate.
• Nickname or alias mismatch. If an Outlook contact uses a personal email (john@gmail.com) while Salesforce stores the work email (john@company.com), EAC treats these as different people.

Before enabling EAC, run a deduplication report on your Contact and Lead objects and standardize email address formatting. Tools like Salesforce Duplicate Management rules (available in Enterprise and above) or a third-party dedup tool should be configured before EAC sync is turned on.

EAC Activity Capture Filtering

Unlike SFO, which synced everything matching the configured data set, EAC includes an exclusion list (called the "Activity Capture Exclusions" setting) that filters which emails are captured. By default, EAC excludes emails sent to or from internal Salesforce addresses, known mass-mail domains, and a configurable list of domains or addresses.

This is operationally important: if your team has domain-specific sync requirements — for example, capturing only emails to and from customers while excluding internal communications — you must configure the exclusion list before enabling EAC. Otherwise, internal emails will flow into Salesforce activity history, polluting reports and violating data hygiene policies.

The exclusion list is configured under Setup > Einstein Activity Capture > Settings > Email Exclusions.

The Sync Model Is Different

SFO used bidirectional sync with explicit conflict resolution — changes in either Salesforce or Outlook propagated to the other, and admins configured whether "Salesforce wins" or "Exchange wins" on conflicts. EAC handles conflict resolution differently:

• Contact sync: EAC resolves conflicts by field-level "last write wins." The most recently modified field value — from either Salesforce or Outlook — takes precedence. There is no admin-configurable "Salesforce wins" policy.
• Event sync: Admins can choose one-way (Salesforce → Outlook, or Outlook → Salesforce) or two-way. On conflict in two-way mode, EAC applies last-write-wins by event field.

Most teams should start with one-way sync (Outlook → Salesforce) for both contacts and events to avoid creating duplicate or overwritten records. Once the baseline is stable and you've confirmed matching logic is working cleanly, evaluate whether two-way is appropriate.

Hybrid Exchange Environment Considerations

The blog and most Salesforce documentation implicitly assume Microsoft 365 (Exchange Online). If your organization runs a hybrid Exchange environment — on-premises Exchange Server connected to Exchange Online — the EAC deployment path is different and more constrained.

EAC requires an authenticated connection to a mail server. For hybrid environments:

• EAC supports Exchange Online mailboxes in a hybrid setup, but mailboxes homed on on-premises Exchange Server are not supported by EAC.
• Users whose mailboxes reside on-prem cannot use EAC for sync. They are limited to manual email logging via Outlook Integration.
• Migrating mailboxes from on-premises Exchange to Exchange Online before enabling EAC is a prerequisite, not an optional step.

Confirm mailbox location for every user in scope before planning EAC rollout. Use the Exchange Admin Center or PowerShell (Get-Mailbox -ResultSize Unlimited | Select DisplayName, RecipientTypeDetails) to identify on-premises vs. cloud mailboxes.

Third-Party Alternatives: When Native Tools Aren't Enough

Salesforce's own migration documentation acknowledges that for some customers, a third-party AppExchange alternative is the best path. Consider this seriously if your org depends on custom object sync, needs activity data stored as physical Salesforce records, or has compliance requirements that EAC's architecture doesn't satisfy.

Cirrus Insight

Cirrus Insight provides a Salesforce sidebar directly in Outlook (and Gmail), automatic email logging that writes data as standard EmailMessage or Task records directly in the Salesforce database, and calendar sync. Unlike EAC, emails are stored as physical Salesforce records — meaning standard SOQL queries, Reports, and Flow automations continue to function exactly as they did under SFO. It also supports relating emails and events to custom objects from the Outlook inbox. Pricing starts at approximately $14/user/month for basic sync, scaling to $49/user/month for advanced features (verify current pricing at cirrusinsight.com; pricing last confirmed Q1 2025).

Revenue Grid

Revenue Grid targets enterprise teams needing granular admin controls, custom-object sync, and full API access to captured data. It writes every interaction directly into standard Salesforce objects — no AWS intermediary. Admins can configure strict filtering rules: syncing only specific domains, excluding internal communications, and mapping complex relationships to custom objects before data writes to Salesforce. Pricing starts at approximately $29–30/user/month (verify current pricing at revenuegrid.com; pricing last confirmed Q1 2025).

For regulated industries where data residency and auditability matter, Revenue Grid's architecture avoids the compliance concerns that EAC's AWS storage model introduces.

Decision Framework

Requirement	Native (OI + EAC)	Cirrus Insight	Revenue Grid
No extra licensing cost	✅ (Standard tier, ≤100 users)	❌	❌
Custom object sync	❌	Partial	✅
Email stored as native SF record	Only with Summer '25 opt-in (irreversible)	✅	✅
Data retention > 24 months	Requires paid tier + support request	✅	✅
Granular sync filtering/exclusions	Limited (domain exclusions only)	Moderate	✅
Hybrid Exchange support	Exchange Online only	Check vendor	Check vendor
Contact dedup on non-email fields	❌	Partial	✅

If your org has simple sync needs, fewer than 100 Outlook users, Exchange Online mailboxes, and no custom object requirements, the native path works. If you hit any of the edge cases above, evaluate third-party options before starting the migration — not after you've already committed to EAC.

Step-by-Step: Planning Your SFO Migration

This migration has two parallel tracks: the UI migration (SFO side panel → Outlook Integration) and the sync migration (SFO contact/event/task sync → EAC or third-party). Treat them as separate workstreams with their own timelines. The UI migration can go live before the sync migration is complete — reps can use Outlook Integration for manual logging while EAC is still being piloted.

Phase 1: Audit Current SFO Usage (Weeks 1–2)

• Pull the SFO login history. From Salesforce Setup, run a login history report filtering for the Salesforce for Outlook application to identify every active user from the last 6 months.
• Document Outlook configurations. Navigate to Setup > Desktop Administration > Salesforce for Outlook and record all sync settings, data sets, field mappings, sync direction preferences, conflict resolution rules, and user assignments. After December 2027, these configurations disappear permanently.
• Identify custom object sync. If any SFO configuration syncs to custom objects, flag this immediately — the native path doesn't support it.
• Identify hybrid Exchange users. Run Get-Mailbox -ResultSize Unlimited | Select DisplayName, RecipientTypeDetails in Exchange Management Shell or PowerShell to confirm which users have cloud vs. on-premises mailboxes.
• Note Outlook folders. Ask reps to confirm which Outlook folders they're syncing. If they're syncing to custom folders, document them — EAC doesn't support custom folder sync.
• Catalog task sync dependencies. Identify any workflows, reports, or automations that depend on task sync data flowing from Outlook to Salesforce Task records.
• Clear unresolved items. Instruct all active SFO users to clear their Unresolved Items queue in Salesforce. These items will not automatically migrate to EAC and will be lost at retirement.

Phase 2: Choose Your Sync Replacement (Weeks 2–4)

Decide whether the native EAC path or a third-party tool fits your org. Key decision points:

• More than 100 Outlook users? You need EAC Licensed (Sales Cloud Einstein, ~$50/user/month) or a third-party tool.
• Custom object sync required? Third-party only.
• On-premises Exchange mailboxes in scope? EAC is not an option for those users.
• Compliance mandates >24-month email retention? EAC Standard and Licensed won't cover it natively.
• Need email data in standard reports and Flows? Enable "Sync Email as Salesforce Activity" (irreversible, 180-day backfill limit) or use a third-party tool that writes native EmailMessage records.

Note: Salesforce provides a Migration Assistant for moving from Lightning Sync to EAC — but this tool does not apply to SFO migrations. The Lightning Sync Migration Assistant detects Lightning Sync configurations and converts them to EAC settings. SFO uses a completely different configuration model (COM-based desktop settings, not Lightning Sync configuration objects), so the tool is irrelevant here. SFO-to-EAC migration is a manual process.

Phase 3: Deploy Outlook Integration (Weeks 3–5)

Roll out the UI replacement before changing the backend sync. This gives reps a working side panel while the sync migration is piloted separately.

1. Work with your Exchange/IT administrator to deploy the Salesforce add-in via the Microsoft 365 Admin Center (Integrated Apps > Deploy Add-in). This enables centralized push to all users without requiring individual installation.
2. In Salesforce, navigate to Setup > Outlook Integration and Sync and enable the integration.
3. Assign email application publisher layouts to ensure users have the correct quick actions (Log Email, New Event, New Contact) in the new side panel. Layouts created for SFO can be reused.
4. Configure the Connected App for Outlook Integration if your org uses IP restrictions or requires explicit OAuth scope grants. The Outlook Integration Connected App must have the following OAuth scopes: api, refresh_token, offline_access. Missing scopes cause silent authentication failures.
5. Pilot with 10–20 reps. Collect feedback on the new side panel, email logging workflow, and record creation process before rolling out org-wide.

Phase 4: Migrate Sync to EAC or Third-Party (Weeks 4–8)

You cannot run SFO and EAC simultaneously for the same user — this creates sync loops and duplicate records. The two products use different matching logic, and when both are active, the same Outlook contact or event can generate multiple Salesforce records. Use a phased rollout instead:

1. Disable SFO sync for a pilot group — don't disable org-wide yet. Remove these users from their SFO configurations in Salesforce under Setup > Desktop Administration > Salesforce for Outlook.
2. Enable EAC for the pilot group. Navigate to Setup > Einstein Activity Capture > Settings. Authenticate using Org-Level OAuth or a Service Account — Microsoft Graph is strongly recommended over EWS (EWS is deprecating in October 2026). Using EWS now means a forced migration in less than two years.
3. Configure the activity capture exclusion list before sync goes live. Navigate to Setup > Einstein Activity Capture > Settings > Email Exclusions. Add internal domains, mass-mail providers, and any addresses you don't want captured to Salesforce activity history.
4. Configure sync direction: start with one-way (Outlook → Salesforce) for both contacts and events. This prevents EAC from overwriting Salesforce records with potentially stale Outlook data during the initial sync window.
5. Monitor for duplicate records over 2–4 weeks. Focus specifically on contacts where the email address in Outlook doesn't exactly match what's stored in Salesforce — these are EAC's most common mismatch cases.
6. Roll out org-wide once the pilot confirms clean data flow, no duplicate surge, and exclusion list is tuned.

Phase 5: Handle the Gaps (Weeks 6–10)

Task Sync Workaround

EAC doesn't sync tasks. For teams that used SFO task sync, the most practical native replacement is a two-component Flow pattern:

1. Salesforce → Outlook direction: Build a scheduled Flow that queries open Task records assigned to each rep and uses the Outlook Integration API action (available in Flow via the "Send Notification" or custom HTTP callout action) to create corresponding Outlook tasks. This requires a custom HTTP callout to the Microsoft Graph Tasks API (Beta: POST /me/todo/lists/{todoTaskListId}/tasks) authenticated via a Named Credential.

2. Outlook → Salesforce direction: There is no native push from Outlook Tasks to Salesforce. Options include: (a) train reps to create tasks directly in Salesforce and sync outward only, (b) use a third-party tool with bidirectional task sync (Revenue Grid supports this), or (c) build a custom integration using Power Automate to watch for Outlook task changes and call the Salesforce REST API.

The honest answer: full bidirectional task sync without a third-party tool requires custom development. If task sync is operationally critical, factor this into the tool selection decision in Phase 2 rather than discovering it in Phase 5.

Custom Object Sync Workaround

If you relied on SFO's custom object sync, the native path has no equivalent. Options:

• Use Salesforce Flows triggered on EmailMessage insert (after enabling "Sync Email as Salesforce Activity") to automatically relate emails to custom objects based on matching logic (e.g., match by contact's Account to a Project record).
• Build a custom integration using the Salesforce REST API and a middleware tool (MuleSoft, Workato, or similar).
• Deploy a third-party tool (Revenue Grid) that natively supports custom object mapping.

Shared Activities

If your org uses the Shared Activities feature (allowing a single email or event to relate to multiple contacts), verify that EAC handles this correctly for your use case. EAC's activity capture creates one activity record per captured email, related to a single primary contact. If SFO was configured to relate emails to multiple contacts via Shared Activities, you will lose that multi-contact relationship in the default EAC configuration.

Historical Data

SFO data that has already synced to Salesforce — including Task records, Event records, and logged EmailMessage records — remains intact in your org after retirement. The retirement does not delete historical data. However, any items in the SFO Unresolved Items queue that have not yet written to Salesforce will be permanently lost when the product retires.

Phase 6: Decommission SFO (Weeks 10–12)

1. Confirm all users are on Outlook Integration + EAC (or third-party) by re-running the login history report and confirming zero SFO logins in the past 30 days.
2. Remove the SFO COM add-in from user desktops — push an uninstall script via Group Policy or SCCM, or let it expire at retirement.
3. Archive the exported Outlook configuration data for compliance records.
4. Update internal documentation, runbooks, and onboarding guides.

SFO Migration vs. Lightning Sync Migration

If you've already read our Lightning Sync migration guide, here's how the SFO migration differs:

	Lightning Sync → EAC	SFO → EAC + Outlook Integration
What synced	Contacts + events only	Contacts + events + tasks + email logging
UI component	None (Lightning Sync was backend-only)	Side panel in Outlook
Migration scope	Sync replacement only	Sync + UI replacement (two workstreams)
Task sync	Not applicable (Lightning Sync never synced tasks)	Requires custom workaround — EAC doesn't sync tasks
Custom objects	Not applicable	Possible with SFO, not with EAC
Migration tool	Salesforce provides a Lightning Sync Migration Assistant	No automated tool; manual configuration required
Hybrid Exchange	Same constraint (Exchange Online only)	Same constraint (Exchange Online only)

The SFO migration is more complex because you're replacing two capabilities simultaneously, not one. The Lightning Sync Migration Assistant that Salesforce provides does not apply to SFO — don't assume you can use it to automate this transition.

What to Do Right Now

December 2027 sounds distant. It isn't. For organizations with 200+ Outlook users, this migration takes 8–12 weeks minimum — and that's if you don't hit custom object sync, task sync, hybrid Exchange, or compliance roadblocks. Any of those adds significant time.

The action items are concrete:

1. Export your SFO login history and Outlook configurations today. This data disappears at retirement.
2. Identify any custom object sync or task sync dependencies. These are your biggest risk areas and drive the tool selection decision.
3. Confirm mailbox locations for all users in scope. On-premises Exchange mailboxes cannot use EAC. Identify those users now.
4. Evaluate whether EAC Standard, EAC Licensed, or a third-party tool fits. The 100-user cap and 6-month retention on Standard are non-negotiable constraints. Run the numbers before assuming Standard works.
5. Plan for two workstreams, not one. The UI migration (Outlook Integration) and sync migration (EAC) should run in parallel but be managed independently.
6. Decide on "Sync Email as Salesforce Activity" before enabling EAC. This irreversible setting determines whether captured emails become queryable EmailMessage records or stay in AWS. The decision has downstream effects on reporting, automation, and compliance.
7. Budget for user training. The new UX is different enough that reps need recorded demos and hands-on walkthroughs — particularly around the Log Email action and the Related To field mapping.

The SFO side panel's action menu has been dead since Summer 2021. The product has received zero new features since June 2019. The longer you stay on it, the more your team adapts to a degraded experience — and the harder the eventual migration becomes.