Several prerequisites are necessary to install the MerciApp add-in for Outlook.

Email addresses used

Microsoft requires that email addresses used in Outlook be based on an Exchange or Microsoft 365 server; without this, it is not possible to use the add-ins.

Operating systems

MerciApp for Outlook is available on Windows 10, Windows 11, macOS (all versions), and Office Online (accessible via your web browser).

The add-in uses the latest technologies to ensure optimal performance, which may sometimes result in incompatibility with older versions. We recommend reading the specifications for each operating system below.

Windows

The level of compatibility varies depending on the edition of your Office suite.

Microsoft 365

Your version of Windows must be 1903 or higher, released in May 2019. You can check which version you are using by following these steps, then reading the number next to "Version." Versions 20H2, 21H1, and 21H2 are also compatible.

Your version of the Office suite must be 1905 or later, released in June 2019. You can check which version you are using by following these steps.

Office 2021 as a one-time purchase

All versions of the Office 2021 suite are compatible, regardless of the release date of the version you are using. However, you will need to install a small, lightweight add-on developed by Microsoft to modernize certain parts of your operating system.

Please refer to the Edge Webview2 section at the bottom of the article.

Office 2013 - 2019

Unfortunately, the MerciApp add-in is not compatible with these versions. As Microsoft has decided to discontinue support for these editions, we cannot commit to developing and maintaining software for them.

macOS

All versions are compatible with MerciApp; however, certain restrictions may be put in place to compensate for possible internal malfunctions in the macOS versions of the Office suite software.

Office Online

All browsers are compatible except Internet Explorer and Edge 1. We recommend that you migrate to a more recent version of these two software programs, using the latest version of Microsoft Edge, which can be downloaded here (https://www.microsoft.com/fr-fr/edge).

Edge Webview2

Microsoft provides a very lightweight program to modernize your various tools; MerciApp relies on these tools to access the latest technologies.

Installation guide

• Go to this link: https://go.microsoft.com/fwlink/p/?LinkId=2124703
• Install the program provided
• Restart Outlook

Updated on: 11/02/2026