Hi @Gerry Peters
Welcome to our forum!
For better research, please provide more details about this case:
What is your account type?
What is your Outlook client version? (File > Office Account > About Outlook). Please make sure you have upgraded your Outlook to the latest version.
Try the following possible solutions:
First, search for the email on the local client, and if the search is found, hover the mouse over the search result to display the directory where the email is stored.
Check your Junk email folder. If it's in that folder, it's possible that the message was marked as spam, or that the sender was blocked.
When you log in to the web mailbox, there is also a problem with the synchronization between the server and the client.
Check if there are any rules that affect message movement.
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