[email-office365] Sending from shared mailbox with Microsoft Graph API

[Philippe-Crest]

Hello,

I am using the Grav premium plugin “Email Office365” with Microsoft Graph API.

According to the FAQ, the plugin supports sending emails from any address that the authenticated Office365 account has “Send As” permission for, including shared mailboxes.

However, in my setup, emails are always sent with the authenticated user as the sender, even when a shared mailbox is specified as the From address.

Context:

• Sending method: Microsoft Graph API (OAuth2)
• App registration with delegated permissions:
  • Mail.Send
  • Mail.Send.Shared
  • User.Read
  • offline_access
    (admin consent granted)
• Authenticated user has “Send As” permission on the shared mailbox
• Desired sender (From): shared mailbox (ateliers@duvertsurlatable.fr)

Observed behavior:

• Outgoing emails always show the authenticated user as the sender
• The shared mailbox never appears as the From address

This suggests the plugin may be using the /me/sendMail Graph endpoint instead of /users/{shared-mailbox}/sendMail.

Could you please clarify:

1. Does the Email Office365 plugin currently support sending from shared mailboxes when using Microsoft Graph API?
2. If yes, is there a configuration option to define the shared mailbox used as sender?
3. Which Graph endpoint is used internally for sending mail (/me/sendMail or /users/{mailbox}/sendMail)?

Thank you for your clarification.

Best regards,

[rhukster]

I will hae to look into this in more detail. I don't actually have a microsoft test setup and when I created this for a client, I had a temporary account to use. I'm currently on vacation and my internet access is spotty. I'm afraid I might not be able to get to this for a while, maybe a couple of weeks until i get back.

[rhukster]

i've confirmed that it is only using the /me/sendMail graph, but i've implemented sending from shared mailboxes if user has "Send As" permission, you will need to re-authenticated to get the "Mail.Send.Shared" scope authorized.

Should be good to go in version 1.0.6

[Philippe-Crest]

Thank you for the clarification and for confirming the behavior.

That makes sense regarding the use of /me/sendMail and the need for the Mail.Send.Shared scope.

I will update to version 1.0.6 once available and re-authenticate to ensure the new scope is granted, then test sending from the shared mailbox.

Thanks for taking the time to look into this.