Add-in Works Fine in Web Word Application but Shows Error in Windows Word Application

[shivyash9]

Issue: Add-in Error in Windows Word Application

I have created a Word Add-in using the yo office generator in React, with the backend served by multiple microservices in Ruby.

When I run all the microservices in HTTPS mode and start the UI with a valid certificate, the Word Add-in loads and works properly on the desktop version of Word on the web (https://www.office.com/launch/Word) for both Chrome and Edge.

However, when I try to open the same Add-in in the Windows Word application, I encounter the following error:

Add-In Error: The content is blocked because it isn't signed by a valid certificate.

Configuration:

• Add-in built with React and backend in Ruby (multiple microservices).
• HTTPS configuration with valid certificate.
• All certificates are installed in the Windows Trusted Root Certification Authorities store, which ensures that they are trusted by the local system and all applications, including the Word desktop app.
• Works fine in the web version of Word (Chrome, Edge).
• Error occurs in the Windows Word application.

What I'm missing or what could be causing this issue?

Any help or suggestions would be greatly appreciated!

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[shivyash9]

The first certificate if for UI of Word AddIn
Rest 3 certificates are for 3 Ruby on Rails Backend microservices.

[Rick-Kirkham]

@emmasab Can you take a look at this? It seems to be more a runtimes issue than an auth issue.

[shivyash9]

Hey Team,
Feel free to let me know if any further detail is required to investigate this case.

[emmasab]

Hi @shivyash9

Could you try the following steps:

• Delete this folder in your user directly: office-addin-dev-certs
• Run the command npx office-addin-dev-certs install
• Ensure it works withnpx office-addin-dev-certs verify
• If it doesn't work, try npx office-addin-dev-certs uninstall followed by npx office-addin-dev-certs install and verify the installation again