You can read the Outlook mailbox of the currently logged in user and any mailboxes that they have access to. If you have a single ID that can access all of the other IDs mailboxes, you would just need to provide the path to each mailbox.
Here is a script that you can use to determine what stores are available.
Thank you for posting your query in the PSC. This looks like an inactive post and hence, we suggest you create a new post for your query. Click on the Write a Post button that’s available on the top right pane of this page. Once created, please reply back here with the URL of the new post.
You may also refer this discussion link as a reference in the new thread
We have also sent you a private message opening up a communication channel in case you have any further questions.