---
title: "What are the permissions required to deploy the add-in"
description: "To deploy an add-in via the Microsoft 365 admin center, certain permissions are required."
url: https://support.signitic.com/en/articles/9561080-what-are-the-permissions-required-to-deploy-the-add-in
collection: "Manage the Outlook Add-in"
updated: 2026-10-09
language: en
alternates: [fr, de, it, pt]
---

# What are the permissions required to deploy the add-in

To deploy an add-in via the Microsoft 365 admin center, certain permissions are required.

### Required Role

Only administrators holding the **Exchange Administrator** role can access the Exchange admin center and manage add-in deployment.

## **❶** What permissions are required?

Without “Permissions” the manifest import fails with the message: _"Error: unable to install the manifest."_

To cover all use cases related to add-in functionalities, the following permission is required:

-   `ReadWriteMailbox` : This permission grants the add-in permission to use these Microsoft API features:
    
    -   `setSignatureAsync` : Signature insertion
        
    -   `addBase64FileAttachmentAsync` : Adding embedded images
        

Without `ReadWriteMailbox` we will encounter errors such as the following:

-   `ReadItem` : Error during the call to `setSignatureAsync`
    
    ![](https://staticfiles.gleap.io/ghelparticle/9Ha8JjpXGXDNskMLVIq4scGJRz40wiPpMldJnYEg3dkIwO6LUAYBcOXGai8As43yCa5WuXKGQnf.png)
    
-   `ReadWriteItem` : Error during the call to `addBase64FileAttachmentAsync`
    
    ![](https://staticfiles.gleap.io/ghelparticle/Sbj4rT0UYBkAu7OezEUbQcQrt9rHhBQaqKRjEBn01Pmkr1rb7rnEXWYZ9Kofq4Rm8lyNin9BB9h.png)
    

## **❷** Why do we request these permissions?

The Signitic add-in intervenes **when composing an email**, to automatically insert a personalized signature. This action requires read and write access to the active message.

The `ReadWriteMailbox` permission allows for:

-   Dynamic insertion of the signature in the body of the email
    
-   Integration of embedded images (logos, banners)
    
-   A seamless experience, without manual action from the user
    

> **Info:** This permission is therefore essential for the proper functioning of our application and is under no circumstances used for malicious purposes. The code is regularly reviewed by Microsoft and is executed in a secure and Microsoft-controlled environment.