How to put Exchange/365 Sent & Deleted Items on Shared Mailboxes into the correct mailbox

When accessing additional mailboxes through Outlook, you will need to apply some registry fixes on the machine that you’re using Outlook on; this will ensure that the Sent and Deleted Items will go into the sent and deleted box for the shared mailbox.

Please see the steps below and add the keys to the registry:

Sent Items:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Preferences

Key – DelegateSentItemsStyle
Type – DWORD
Value – 1

Deleted Items:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\Preferences

Key – DelegateWastebasketStyle
Type – DWORD
Value – 4

Once this is done, please restart Outlook and test the behaviour of the folders.