Forum Discussion

kazim-mir's avatar
kazim-mir
Copper Contributor
Feb 20, 2026

Publish an Excel Add-in by just submitting the add-in manifest to Microsoft Marketplace

I am working on Excel Add-in built using the react template. We are planning to host the add-in code on our domain and update the manifest to point to the URL for our domain. Can I just submit the add-in manifest to Microsoft to publish it in Microsoft Marketplace?

excel
microsoft 365
microsoft 365 apps
office 2016
office 2019
office 365
Office for the web

1 Reply

  • NikolinoDE's avatar
    NikolinoDE
    Platinum Contributor
    Feb 26, 2026

    The short answer is yes, the manifest file (an XML file) is the core technical component required for submission. However, you cannot simply "upload the file" and be done. You must go through the Microsoft Partner Center portal, and the manifest must meet strict validation criteria.

    Since you are self-hosting the React code on your own domain, here is the step-by-step reality of what is required to get your add-in into the Microsoft Marketplace (AppSource).

    Before you log in to submit, you must have the following ready. If these are missing, the automated validation will fail immediately:

    • HTTPS is Mandatory: Your domain must have a valid SSL certificate (no self-signed certs). All SourceLocation URLs in the manifest must be https://, not http://.
    • Privacy Policy & Terms of Use: You must host two static HTML pages on your domain (or a legal page) stating your privacy policy and terms of use. The manifest requires direct URLs to these.
    • High-Resolution Assets: You need specific PNG icons (128x128, 64x64, etc.) and screenshots of the add-in running in Excel for the store listing.
    • Partner Center Account: You need a verified developer account. There is usually a one-time 5−10 registration fee (for individual accounts) to open a Partner Center account.

    Preparing the Manifest for Self-Hosting

    Since you are using the React template and hosting it yourself, you need to ensure your manifest.xml is configured correctly for production

    Submission Process (Partner Center)

    You do not send the file via email or a form; you use the Office Add-ins submission tool in Partner Center.

    Critical "Gotchas" for Self-Hosted React Apps

    Since you control the server, Microsoft holds you responsible for the following:

    • CORS/CSP: Your web server must be configured to allow the add-in to be iframed inside Excel Online and Windows/Mac clients. Ensure your HTTP headers allow framing from *.officeapps.live.com and *.microsoft.com.
    • Availability: If your server goes down, Microsoft may remove your add-in from the store.
    • Updates: When you update your React code and deploy to your server, the add-in in the store updates instantly for all users. You do not need to resubmit the manifest to Microsoft for code bug fixes (unless you change the UI structure or require new permissions).
    • Telemetry: You are responsible for handling user data (GDPR/CCPA). The manifest asks if you collect data; answer truthfully.

    To publish right now:

    1. Build your React app (npm run build).
    2. Deploy to a secure HTTPS server (AWS S3+CloudFront, Azure Blob, Heroku, etc.).
    3. Update manifest.xml SourceLocation to point to that HTTPS URL.
    4. Create a Privacy.html and Terms.html and link them in the manifest.
    5. Log in to Partner Center, create the listing, and upload the XML.
    6. Pay the submission fee (if applicable to your account type) and submit for certification.

    Verdict: You are correct—you only submit the manifest, but that manifest acts as a pointer to your code. Microsoft validates the pointer, but your server hosts the actual payload.

     

    I hope this information can help you with your project.