Hi @michael lustig ,
As qasimali mentioned, in the point of Outlook client, we could manage it via "DelegateSentItemsStyle " registry value, based on my tests, it could work for my shared mailbox, for your reference, here are my detailed steps:
- create the DelegateSentItemsStyle value in registry key :
Location: Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Preferences
Type: DWORD
Value: DelegateSentItemsStyle
Data: 1
(Note: Serious problems can occur if you modify the registry incorrectly. Before making changes, back up the registry to restore it in case something goes wrong.)
- restart your Outlook and ensure you are working in cached exchange mode
For more information, please refer to this document: Set the DelegateSentItemsStyle registry value on the Outlook client
Also, if you are an exchange administrator, you could also try to follow the Method 1 to manage it via powershell :
Hope that would be helpful to you.
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