If you’ve installed Office 2016 since its release on September 22, and are using Microsoft Outlook 2016 with any IMAP-enabled accounts, you might have experienced a bug.
The Office 2016 upgrade does a great job retaining previous settings, particularly for Outlook 2016. The Office 2016 upgrade is probably one of the cleanest upgrades ever, removing previous versions of Office completely. But, after installation, there’s a bug in Outlook 2016 for IMAP email accounts where you cannot delete emails from the Inbox, and the bug happens to be because of a configuration in the email account’s Advanced settings. What worked before doesn’t work now and you’ll need to make a slight modification to get the IMAP account working correctly.
To get there to make the setting change:
In Outlook 2016, go to File – Account Settings.
Open the IMAP account and then choose the More Settings… option.
Make sure the Deleted Items settings match the following…