Frequently Asked Questions

Contact Orfys Technologies at info@msofficeaddin.com or via the /contact page. We are a Microsoft Partner Network member with 500+ Office Add-in projects delivered since 2015. Project quotes are returned within 24 business hours. Engagements start from $3,000 USD.

Office Add-ins use HTML, CSS, and JavaScript via the Office.js API. They run cross-platform on Windows, macOS, and Outlook on the Web with no local installation required. COM Add-ins are legacy .NET/Windows-only extensions requiring administrator rights and do not run on Mac or Web. Microsoft has deprecated COM add-in development in favour of Office.js.

We follow the Office.js Mailbox requirement set model (currently Mailbox 1.10 for Microsoft 365). A typical Outlook add-in takes 4–10 weeks: 1 week discovery, 1–2 weeks design, 3–6 weeks build, 1 week AppSource submission (3–7 business day Microsoft review). We handle Azure AD SSO via MSAL OBO flow, manifest configuration, and AppSource certification.

Simple task-pane add-ins (read/write data, basic UI): 2–4 weeks. Add-ins requiring Microsoft Graph API, SSO, or CRM integration: 6–10 weeks. Complex enterprise solutions with multi-tenant Azure infrastructure: 10–16 weeks. All timelines include AppSource submission and post-launch support.

All add-ins we build support Microsoft 365 (Current, Monthly Enterprise, and Semi-Annual channels), Office 2021, and Office 2019. Support for Office 2016 depends on the specific Office.js requirement sets used and is confirmed per project. Add-ins do not support Office 2013 or earlier.

Enterprise deployment uses Centralized Deployment via the Microsoft 365 Admin Center — admins push the add-in to all users or specific groups with no end-user installation required. Public distribution uses Microsoft AppSource. SharePoint App Catalog is the third option for SharePoint-specific add-ins. All three methods use the same Office Add-in manifest file.