Hi @Elie K ,
Dragging and dropping messages and attachments is currently not supported in New Outlook for Windows, and this work is in progress and will be available in the future. As a workaround, 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. someone has already submitted this feedback, you can vote for him through this link, if you have any feedback or additional suggestions for improvements, please post the functions you expect and your sincere suggestions.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.