Hi @Brian Chervy ,
Welcome to our forum!
Does this problem happen to all users or some special users?
And does this issue occur recently? If so, have you done any specific operations before that?
From the Outlook application, new incoming emails are not displayed in the inbox, however when searching, it appears.
AS I know, if the email is found, we can place the mouse on the search results to display the storage folder of the email. Please check if the email is in another folder.
Test in online mode : OK , but user experience is not comfortable with the high latency
Do you mean that the issue occurs when the cache mode is turned on?
If so, I noticed that after restarting Outlook, new emails can be received in Outlook 2016, please try to send/receive emails manually in cache mode and check if new emails can be synchronized. If you can receive updated messages, it is likely to be related to the sending / receiving frequency. It is recommended that you try to set this to a smaller time(Send/Receive>Send/Receive Groups>Define Send/Receive Groups).
If above doesn't work, considering that the current outlook data file is damaged or the profile may be damaged, it is suggested that you could try to create a new profile(Control Panel>Mail>Show Profiles>add) and add the account to check if there are any differences.
Hope the above help!
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