Hi @Rudy Magcalas ,
According to my test, I can preview attachment in new outlook, select the down arrow to the right of the attachment title. In the menu that appears, choose and select preview, a preview window opens showing the attached file on the left side and the email message body on the right.
The new Outlook is not yet complete, and some options may not be available or work as expected. You can switch back to the classic Outlook at any time by clicking the toggle button in the top right corner of the window.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future. You can help us improve the product by providing feedback about your experience with the app.
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