Despite mainstream support ending, many small and medium-sized law firms continue to use Office 2016 for Mac due to its stability, familiar interface, and offline capabilities. But how can its use be reconciled with increasingly complex regulatory requirements and evolving security expectations?
This blog explores the main reasons why law firms still use Office 2016, the associated risks, compliance implications, and how to bridge the gap between legacy and compliance without a full upgrade.
Why do law firms still use Office 2016 for Mac
One-time licence model
Unlike the subscription billing of Microsoft 365, Office 2016 for Mac was sold with a perpetual license, making it attractive to budget-conscious firms. Law offices that prefer an upfront investment over recurring costs appreciate the predictability.
2. Offline functionality
Legal professionals deal with sensitive, confidential, and privileged data. Many prefer software that operates offline by default, reducing exposure to cloud-based vulnerabilities.
3. Compatibility with legacy documents
Law firms with decades of files they appreciate Office 2016's native compatibility with old files .doc, .xls e .ppt. Consistent behaviour from macros, form fields and formatting is fundamental for legal documents and contracts.
4. Stability and familiarity
The user interface of Office 2016 is intuitive for legal assistants, clerks and lawyers—many of whom have been using Office products for over a decade. This eliminates the learning curve associated with newer versions.
5. Integration with existing case management systems
Many legacy legal systems (case management, billing, document management) were designed to operate with Office 2016 APIs. Updating Office would risk breaking compatibility or require costly adaptations.
Compliance considerations: risks of using Office 2016 in 2025
Although the reasons for maintaining Office 2016 are clear, there are significant risks that law firms must manage to remain compliant with regulations such as:
- GDPR (EU)
- HIPAA (lavoro legale legato alla sanità negli Stati Uniti)
- SOX (for studies assisting listed companies)
- ABA Model Rules of Professional Conduct
1. Lack of security updates
Microsoft ended extended support for Office 2016 in October 2023. Without security patches, law firms are more vulnerable to malware, ransomware, and zero-day attacks.
2. Cloud compatibility challenges
Office 2016 has limited support for modern cloud authentication protocols (OAuth 2.0, Modern Auth), which can compromise secure access to OneDrive, SharePoint, or encrypted email.
3. Lack of Data Loss Prevention (DLP) tools
Modern versions of Office include built-in DLP, email encryption, and information rights management. Office 2016 lacks these, putting sensitive data at risk during transmission or sharing.
4. Limited tracking and logging
Office 2016 does not offer the detailed auditing functionalities present in Office 365. For firms that need to monitor document access or modifications, this can be a significant drawback.
Strategies for remaining compliant using Office 2016
If your practice decides to keep Office 2016 for Mac, here are practical ways to ensure compliance:
2. Improve endpoint security
Install advanced-level antivirus, firewall and Endpoint Detection and Response (EDR) software on all machines with Office 2016. Ensure that macOS and third-party tools are always updated.
2. Use encrypted local storage
Configure the documents to be stored only on encrypted volumes or partitions (FileVault on Mac). Avoid saving files in insecure or public folders.
3. Implement network-level protections
Route email and web traffic through a secure gateway or firewall that includes content filtering, malware scanning, and DLP functions.
4. Limit user access and privileges
- Run Office apps with non-administrator accounts
- Apply robust password policies
- Disable macros unless they are signed and verified
5. Use secure email gateways for confidential documents
As Outlook 2016 does not have modern encryption tools, use third-party secure email platforms such as Mimecast or Zix to send and receive privileged communications.
6. Best practice for document management
Utilise a secure, on-premises or hybrid document management system, such as Worldox or iManage, that can integrate with Office 2016 and enforce compliance policies.
7. Policy training and auditing
Train staff on how to recognise phishing, handle confidential documents, and comply with data privacy laws. Use manual or software audits to log activities.
8. Regular and secure backups
Daily backups of Office files should be encrypted and stored in isolated or offline systems to protect data from loss or ransomware.
Legal workflows where Office 2016 still excels
Despite its age, Microsoft Office for Mac 2016 continues to offer good performance in key legal functions such as:
- Drafting and formatting contracts in Word
- Managing legal research notes in Excel
- Preparing presentations for legal cases
- Planning and managing appointments with Outlook
- Template-based module modification
Many studies also use custom macros in Word or Excel to automate case logs, calculate deadlines, or generate reports.
Alternatives for law firms not ready for Office 365
If a full migration to Microsoft 365 or Office 2021 isn't yet possible, here are hybrid approaches:
➤ Use Office 2016 with a cloud gateway
Continue to use Office 2016 offline, but integrate cloud tools for sharing and backup (e.g. Tresorit, pCloud or Dropbox Business).
➤ Implement a Virtual Desktop Infrastructure (VDI)
Install Office 365 in a secure remote environment (like Azure Virtual Desktop) and allow limited access while keeping Office 2016 for local work.
➤ Use parallel installations
Keep Office 2016 for local formatting and use, but install Office Online or 365 in browsers for secure collaboration.
When to finally update
The time will come when even the most established legacy systems will need to be replaced. Law firms should consider upgrading when:
- Practice management tools stop supporting Office 2016
- macOS updates break compatibility
- Regulatory audits flag outdated software
- Compliance tools must be integrated (e.g. auto-redaction, change tracking).
