I have an Exchange 2013 environment that I recently finished migrating from Exchange 2010.  There are no longer any Exchange 2010 servers in the environment.  We have two mailboxes to which we have grated "Full Access" to four users (the same four users for each mailbox).  These users have successfully added the two mailboxes to their OWA by clicking their name and selecting "Open another mailbox".  This all works as expected.  The problem is with unread message counts.  The users see their own mailbox folders' unread counts update periodically as expected, but folders in the additional mailboxes never show an unread count until the user clicks the folder.  I have been searching for days on this and am completely baffled.  We do not allow our users to use Outlook and have no intention of doing so.  Any help is greatly appreciated!

Hi Rekkanoryo,

Base on my knowledge, if you select "open another mailbox", the secondary mailbox will be opened in a separate browser window, not add to the primary mailbox.

I recommend you try the following method to add the secondary mailbox so it displays under your primary mailbox in Outlook Web App, and then check if there is the same issue:

1. Sign in to your account in Outlook Web App.

2. Right-click your primary mailbox in the Folder pane, and then click Add shared folder.

3. In the Add shared folder dialog box, type the name of the shared mailbox, select the name, and then click Add.

Best regards,

 

Yes, you are correct that opening the mailbox opens a new browser window.  I removed the shared mailbox by right-clicking it and clicking "Remove Shared Folder" and did the "Add Shared Folder" step you described.  This gives us exactly the appearance that I was describing earlier.  The secondary mailbox appears in the folder view at the left of the browser window and when expanded, the folder list appears.  But the unread counts for folders in the secondary mailboxes only update when the user performs an action on those folders, such as clicking on the folder and refreshing or clicking on the folder and deleting or opening (by double-clicking) a message.  Unread counts for the user's own mailbox work exactly as expected.

I unmarked the answer because it does not resolve the problem.  The secondary mailbox unread counts do not update automatically like the primary mailbox does.