Some organizations operate in highly restricted Office 365 environments such as GCC, GCC High, or DoD. These environments are designed for federal, state, and local government agencies or contractors handling sensitive or regulated data.
While these environments offer important security and privacy protections, they also come with significant platform limitations compared to commercial Office 365.
➡️ Learn more about Office 365 Government environments here
Why CloudExtend Add-ins Are Not Supported in GCC / DoD
CloudExtend’s Office add-ins ExtendSync and ExtendInsights are built using modern Microsoft Office Add-in architecture, which depends on:
Microsoft 365 commercial cloud APIs
Standard Office web add-in infrastructure
Cross-origin resource access
Modern browser engines (Edge WebView2, Safari WebKit, etc.)
External endpoints required for authentication, licensing, and real-time communication
Government cloud environments, however, limit or block many of these resources, including:
External service endpoints
Authentication flows not hosted in the government cloud
Script and content permissions restricted by GCC/DoD security policies
Required infrastructure components that do not exist in sovereign clouds
While it is technically possible to deploy add-ins in these environments, the current architecture of CloudExtend apps cannot run inside GCC High or DoD tenants.
Why We Can’t Simply Enable Support
Supporting GCC/DoD would require:
A complete rebuild of our authentication architecture
Hosting all CloudExtend services in a government-certified cloud
New compliance frameworks (DFARS, FedRAMP, ITAR considerations)
Replacing or reengineering Microsoft dependencies not available in GCC High
Supporting restricted browser engines and blocked API calls
Ensuring all communication is contained within sovereign boundaries
Because of these unknowns and ongoing limitations, CloudExtend cannot currently guarantee reliable functionality in GCC or DoD environments.
Official Response
At this time, CloudExtend add-ins are not capable of running in Office 365 GCC High or DoD environments.
Supporting these environments would require significant architectural changes, which we may evaluate for future roadmap consideration.
Need Help or Have Questions?
If you are unsure whether your tenant is GCC/GCC High or want to discuss alternatives:
💬 Chat with us (bottom-right of this page)
📧 Email cloudextend-support@celigo.com