Open your organisation’s WSD app to follow these steps. Your organisation’s settings and permissions may change which controls you see.

How to do it

  1. 01

    Open Settings → Software & Apps and download the Outlook add-in, or use Admin → Company Settings → Microsoft 365.

  2. 02

    In Outlook, open Apps or Get Add-ins → My add-ins → custom add-ins → Add from file, and upload the manifest.

  3. 03

    Open a new message, choose the branded Secure add-in and sign in when prompted.

Reviewed 30 September 2026Report an issue with this guide ↗