When hitting the send/receive-button the folder structure changes. When I open Outlook for Mac 2011 I see my two IMAP-Accounts and the mails on my computer with the sub-structure I created. As soon, as I hit the send/receive-button I see only the inbox (which displays the number of mails of one of my IMAP accounts) but the other accounts as well as the substructure is not displayed any more. How can I stop this (I want the original view)?

This strange behavior started, when I added a new IMAP-account.

I use MS Outlook for Mac 2011 (version 14.6.5) on a MacBook Pro with OS X El Capitan 10.11.5.