Microsoft shared mailbox OAuth: protocol support is not connector support

Define the decision

Microsoft documents an OAuth pattern that authorizes a user and uses the shared mailbox address in the XOAUTH2 username. Zintara’s reviewed standard connection does not expose that separate shared-mailbox identity selection.

Work through the procedure

1. Identify the authorizing user and intended shared mailbox.
2. Have the administrator verify the required mailbox permissions.
3. Confirm whether the deployed application supports the distinct shared identity.
4. If unsupported, choose an approved supported mailbox arrangement rather than assuming webmail access carries over.

Worked example

The following is a synthetic example for this procedure, not a customer result or performance benchmark.

Authorizing user: [email protected]
Intended mailbox: [email protected]
Required distinction: user token plus shared mailbox protocol identity
Reviewed Zintara limitation: no separate shared-mailbox selector in the ordinary connection flow

Read the result

This boundary matters for both sending and reply ingestion. A connection that signs in the operator can otherwise create misleading confidence while operating the wrong mailbox.

Check before moving on

1. Inspect the connected account address.
2. Validate the received From and the mailbox receiving replies.

Limits and next action

Do not create or share a password for a shared mailbox as an improvised substitute. Use a supported permission model and document the current product limitation.

Source: Microsoft: shared-mailbox OAuth protocol pattern