Using Classic Outlook on Windows for personal email, calendar, and contact management
Hello Doron Fine,
Good day! Thank you for posting in the Microsoft Community. We will be happy to help you.
Based on your description I understand that emails from one sender arrive in the inbox, but after opening the letter it automatically goes to the Deleted Items folder even after clearing the rules and it happens in the web version as well. Appreciate your efforts that you already checked message for the most possible causes of this issue, so it could be something related with backend side and to investigate this query further need more resources. As we belong to community, we have limited permission, so it is suggested to open ticket with Microsoft Technical team, so they can check remotely and assist you further. At this point, I highly appreciate your kind understanding and co-operation.
To open ticket: Get support - Microsoft 365 admin | Microsoft Learn
We are looking forward to your reply. Thank you for your valuable time and cooperation.
Sincerely,
Simbarashe | Community moderator.