Issue Summary

If you have a shared mailbox A and create an incoming mail channel for this in JSM using the Microsoft Graph API. When you authorise the connection using account B, Jira will instead process incoming mail from account B rather than the defined account A.

This is reproducible on Data Center: yes

Steps to Reproduce

1. Install JSM that supports Graph API
2. Setup an Oauth integration with Azure, that uses Graph API permissions
3. Create an incoming mail channel in JSM that uses the Microsoft Graph API protocol and is pointed to a shared mailbox
4. Authorise the connection with a second user that has delegated access to the shared mailbox
5. Watch Jira process mail from the second user, not the shared mailbox

Expected Results

Jira should function as normal and process incoming mail from the shared mailbox

Actual Results

Jira processes incoming mail from the authorising account

Workaround

• Turn the shared mailbox into an account, so it can authorise the connection.
• Use IMAP/POP protocols for your incoming mail
• The client credentials grant flow for the Oauth 2.0 integration implemented for the Incoming/Outgoing Mail Server has been implemented in Jira in version 9.17 under the feature JRASERVER-74324. Please use the steps from the following article as a workaround: How to setup Azure mail using Graph API with client credentials (application permissions) in Jira Data Center. For many organisations, this might be the preferred method for integration as well.