Error Sideloading Outlook Add-in: "The file assets/color.png could not be found in the app package

Question

I am developing an Outlook Task Pane add-in using the Teams Toolkit in Visual Studio Code. I've followed the standard steps to set up the project and ensure all necessary files are in place. However, when I attempt to sideload the add-in, I encounter the following error:

Error: Unable to start debugging.

Error: Unable to sideload the Office Add-in. Error: Command failed: npx @microsoft/teamsapp-cli install --file-path "C:\Users\anike\AppData\Local\Temp\manifest.zip" (node:18140) [DEP0040] DeprecationWarning: The punycode module is deprecated. Please use a userland alternative instead. (Use node --trace-deprecation ... to show where the warning was created) (×) Error: M365.PackageServiceError: Request failed with status code 400 (tracingId: 00-d82fe7c826ffa56722d999e4ce9adabf-a4b25a1dbff506db-00) BadRequest: Manifest schema is not valid. Errors: The file assets/color.png could not be found in the app package.

I followed the typical setup process for creating an Outlook Task Pane add-in using the Teams Toolkit. I verified that all required assets are in place and correctly referenced in the manifest.json file. Despite these checks, the sideloading process fails with a file not found error for assets/color.png. I expected the add-in to load successfully in Outlook for testing and development purposes.

Can someone help me understand why this error is occurring and how to resolve it? Any insights or suggestions would be greatly appreciated. Thank you!

Answer 1

Hi @Agus Paterlini ,

When you get a chance, could you please try moving the color.png file from the assets folder to the root of your add-in project? Then, update the image path in your manifest accordingly.