Office Online Server support ends on December 31, 2026.
Evaluate a self-hosted online office for browser-based document viewing and editing without moving sensitive business documents to a public cloud.
Deploy within your own infrastructure.
View and edit Office files directly in the browser.
Connect with SharePoint, DMS, ECM, and more.
Validate compatibility before you commit.
Office Online Server currently provides browser-based viewing and editing capabilities for Office files across SharePoint Server and other WOPI-compatible environments.
When support ends on December 31, 2026, organizations that continue operating OOS will no longer receive new security updates, non-security updates, or Microsoft assisted support.
For organizations that cannot move document workloads to Microsoft 365, the challenge is not simply replacing a server. It is maintaining document viewing, editing, permissions, integrations, and operational control across the existing enterprise environment.
No new security updates or Microsoft-assisted support after end of support.
Public cloud migration may not meet every organization's security, sovereignty, or architecture requirements.
Existing SharePoint, DMS, ECM, and business application workflows still need document viewing and editing.
Maintain controlled document environments for public records, internal collaboration, and sensitive administrative workflows.
Support browser-based document workflows while retaining control over data location, permissions, and infrastructure.
Integrate document viewing and editing into private systems used for sensitive operational and research information.
Connect document capabilities to internal portals, DMS platforms, project systems, and distributed enterprise workflows.
Continue operating the existing environment after support ends.
Considerations:
• No new Microsoft security updates
• No assisted support options
• Increasing operational and compliance risk
Migrate document workloads and collaboration services to Microsoft’s public cloud.
Suitable when:
• Public cloud deployment is acceptable
• Existing systems can be migrated
• Data residency and integration requirements can be met
Replace OOS document services while maintaining deployment within your own infrastructure.
Suitable when:
• Documents must remain on-premises
• Existing enterprise systems must be retained
• Browser-based Office editing is still required
Office Online Server | Thinkfree Office | Microsoft 365 | |
|---|---|---|---|
On-premises | |||
Thinkfree Office provides browser-based document viewing and editing capabilities that can be deployed within an organization's own infrastructure.
It is designed for enterprises and solution providers that need to integrate Office document capabilities into document management systems, private cloud platforms, and business applications.
Rather than forcing every document workflow into a public cloud, Thinkfree enables organizations to evaluate a self-hosted architecture based on their security, integration, document compatibility, and operational requirements.
DOCX, XLSX, PPTX Support
Co-editing
(Real-time)
PDF Conversion & Export
API / SDK / WOPI Integration
Evaluation Area | Office Online Server | Thinkfree Office |
|---|---|---|
Deployment model | On-premises | Self-hosted / On-premises / Hosted-API |
Supported | Supported | |
Supported | Supported | |
DOCX support | Supported | Supported |
XLSX support | Supported | Supported |
PPTX support | Supported | Supported |
WOPI support | ||
Co-editing | Supported | Supported |
PDF conversion | Supported | Supported |
Data location | Customer-controlled | Customer-controlled |
No two OOS environments are identical. Integration methods, document complexity, authentication, permissions, custom applications, and operational requirements can vary significantly. Thinkfree evaluates replacement feasibility using your actual architecture and representative business documents.
SharePoint, WOPI host, DMS, ECM, or custom application integration
Layout, fonts, tables, charts, formulas, animations, and embedded objects
Open, edit, save, rename, download, convert, and collaborate
Validation of server configuration, network environment, storage, and deployment requirements
Deployment topology, scaling, load balancing, storage, and network requirements
Monitoring, updates, support, backup, recovery, and lifecycle management
Microsoft lists December 31, 2026 as the end-of-support date for Office Online Server. After support ends, Microsoft states that new security updates, non-security updates, assisted support options, and online technical content updates will no longer be provided.
An existing OOS environment may continue to operate technically, but it will no longer receive the support and updates described in Microsoft’s lifecycle policy. Organizations should assess the resulting security, compliance, support, and operational implications.
No. Microsoft 365 may be suitable for organizations that can move document workloads to the public cloud. Organizations that must retain documents and applications within their own infrastructure can also evaluate self-hosted alternatives.
Replacement feasibility depends on your current architecture, connected host systems, required OOS capabilities, document complexity, and authentication model. Thinkfree recommends a technical assessment and PoC before migration.
WOPI integration feasibility depends on the host implementation, required operations, and document workflows. Thinkfree reviews each environment through a technical assessment or PoC.
Thinkfree supports browser-based handling of major Office document formats, including DOCX, XLSX, and PPTX. Exact viewing, editing, conversion, and collaboration capabilities should be validated against representative business files.
Yes. Thinkfree Office is designed for deployment within customer-controlled infrastructure or private cloud environments.
During a PoC, representative documents are tested for layout, fonts, formulas, charts, tables, images, animations, embedded objects, editing behavior, saving, and conversion.
The timeline varies according to integration complexity, infrastructure requirements, document testing, security review, and user acceptance. A technical assessment is required to define a realistic migration plan.
In many cases, the existing host application can remain in place while the document viewing and editing layer is replaced. Feasibility depends on the current integration architecture and required workflows.
A production replacement may require architecture review, integration work, document testing, security approval, and user validation.
Start with a structured assessment of your current environment.
