Sideload Excel Add-In on MacOS Sierra

Table of Contents

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In a previous post we looked at the process of generating an Excel add-in and using mkcert to create private certification authority (CA) trusted by browsers. In this post, we continue the journey of developing office add-in by looking at the steps involved in side loading our add-in in an Excel host.


The add-in how to guide for iPad and Mac sets out the following prerequisites:

  • A Mac running OS X v10.10 “Yosemite” or later with Office for Mac installed.

  • Excel for Mac version 15.19 (160206).

  • The manifest .xml file for the add-in you want to test.

In this post, we will utilize the following:

  • A Mac running macOS High Sierra v10.13.3

  • Excel for Mac version 16.16.5 (181209)

  • Manifest.xml for the Excel add-in that we created in the previous post

Steps to sideload our Excel add-in

  1. Open Terminal window and verify that wef folder exists on your computer by running the following command.

    cd /Users/${USER}/Library/Containers/
  2. If a No such file or directory message is displayed, then run the following commands from the terminal to create the folder and navigate to the newly created folder:

    mkdir /Users/${USER}/Library/Containers/
    cd  /Users/${USER}/Library/Containers/
  3. Copy manifest.xml file of your Excel add-in to the wef folder. If you followed the previous post on generating an office add-in, then your copy command will be similar to the following:

    cp ~/office-js/expense-updater/manifest.xml .

    If you are testing more than one Excel add-in, rename the add-in manifest.xml file while copying to avoid overwriting a manifest file for another add-in.

    cp ~/office-js/expense-updater/manifest.xml ./expense-updater.xml
  4. Change directory to the root of your Excel add-in and start your add-in server

    cd ~/office-js/expense-updater
    npm start
  5. Close the Excel application if it is already running. Make sure your completely quit the application.

  6. Open your Excel workbook

  7. Choose Insert from the menu

  8. Click on the drop-down arrow next to My Add-ins and select your Excel add-in.

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  9. Your Excel add-in will now load and a callout will be displayed


  10. Click on the Got it button to dispose the callout.

  11. Click on your Excel add-in button to sideload the add-in.

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