Microsoft 365 and Windows Features Retiring in 2025: What IT Admins and Users Need to Know

Microsoft has announced several feature retirements and deprecations coming to Windows 11 and Microsoft 365 in 2025, marking another step in the company's modernization efforts. These changes will impact both end-users and IT administrators, requiring preparation for smoother transitions.

Major Features Being Retired in 2025

1. Legacy Authentication Protocols

Microsoft will completely disable Basic Authentication (SMTP, POP, IMAP) across all Microsoft 365 tenants by late 2025. This follows years of gradual phasing out due to security concerns:
- Already disabled for newly created tenants
- Affects older email clients and devices
- Modern Authentication (OAuth 2.0) becomes mandatory

2. Windows 10 Support Ends

While not a feature retirement per se, Windows 10 reaches end-of-support on October 14, 2025:
- No more security updates after this date
- Windows 11 becomes the only supported consumer OS
- Enterprise customers can purchase Extended Security Updates

3. Classic Outlook for Windows

Microsoft will retire the legacy desktop Outlook client in favor of the new Outlook for Windows:
- Scheduled for second half of 2025
- Web-based architecture with better performance
- Lacks some advanced features of classic Outlook

Impact on Business Environments

IT Administration Changes

• PowerShell modules for older Exchange Online versions will stop working
• Azure AD Graph API will be fully deprecated
• System Center Configuration Manager (SCCM) features will migrate to Microsoft Intune

End-User Experience Shifts

• Cortana will be completely removed from Windows 11
• WordPad will no longer be included in Windows installations
• Steps Recorder (PSR.exe) replaced by modern screen capture tools

Preparing for the Changes

Migration Checklist for Businesses

1. Audit all devices and services using legacy authentication
2. Update or replace applications relying on deprecated APIs
3. Train staff on new Outlook and authentication methods
4. Plan Windows 11 upgrade path for all Windows 10 machines
5. Review Microsoft 365 license requirements for new features

Timeline of Key Dates

Why Microsoft is Making These Changes

These retirements align with Microsoft's Secure Future Initiative, focusing on:
- Reducing attack surfaces by eliminating outdated code
- Standardizing on modern authentication protocols
- Consolidating products to reduce maintenance overhead
- Pushing adoption of cloud-native solutions

Alternatives and Replacement Features

For each retired feature, Microsoft offers modern alternatives:
- Basic Auth → Conditional Access with MFA
- WordPad → Word Online or Office desktop apps
- Steps Recorder → Xbox Game Bar or Snipping Tool
- Cortana → Windows Copilot (AI assistant)

Expert Recommendations

Industry analysts suggest:
- Start testing Windows 11 now to identify compatibility issues
- Use Microsoft's readiness tools to assess impact
- Consider this an opportunity to modernize workflows
- Budget for necessary hardware upgrades where needed

Looking Beyond 2025

These retirements signal Microsoft's broader strategy:
- Accelerated move to cloud-first solutions
- Tighter integration between Windows and Microsoft 365
- Increased focus on AI-powered features
- Reduced support for on-premises enterprise solutions