Gartner Research

Guidance for Exchange Online (Office 365) Implementations

Published: 21 January 2020

ID: G00450957

Analyst(s): Mark Cortner , Patrick Borka


Exchange Online implementations are mainstream, yet retain significant complexities ranging from migrations, to changes to security and compliance strategies, to managing the flow of service updates. Application technical professionals must be aware of gotchas to avoid and changes to Office 365.

Table Of Contents

Problem Statement

The Gartner Approach

  • What’s New in This Framework Update

The Guidance Framework

  • Prework Step 1: Map the Current State of Email
  • Prework Step 2: Analyze the Business Case for Exchange Online
    • Cost
    • Functionality
    • Integration
    • Risk
    • Segmentation
  • Migration Strategy
    • Migration Methodologies
    • Exchange Online Limits
    • Exchange Online Migration Throttling
  • Identity
    • Modern Authentication
    • Distribution Lists
    • Office 365 Groups
  • Hybrid
    • Implementing Hybrid With Exchange Online
    • What Does Not Work With a Hybrid Implementation
    • Why to Not Decommission Exchange Server With Hybrid
    • Scenarios When It’s OK to Decommission Exchange Server
    • Additional Hybrid Exchange and Multicloud Email Routing Options
  • Data Migration
    • Mailboxes
    • Public Folders
    • Archives
    • Multi-Geo Support
    • Tenant-to-Tenant Mailbox Migration
  • Backup
    • Exchange Online’s Architecture
    • Scenarios When Organizations Ask About Backups
    • Requirements to Assess for Third-Party Backup Solutions
  • Records
    • Retention Tags
    • In-Place and Litigation Holds
  • Security
    • Basic Malware Protection
    • Advanced Security Services
    • Data Loss Prevention (DLP)
    • Encryption
  • Integrations
    • SMTP Limits
    • APIs
    • Outlook Client Plug-Ins
    • Microsoft Teams
    • Exchange Online Unified Messaging
  • Management
    • Exchange Admin Center (EAC)
    • Office 365 Admin Center
    • Office 365 Security and Compliance Center
    • PowerShell
  • Clients
    • Outlook Client
    • Outlook on the Web
    • Outlook for Mac for Office 365
    • Email Clients to Avoid With Exchange Online
  • Mobility
    • Mobile Clients
    • Mobile Management
  • Exit Strategy

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