MC556157 Microsoft is retiring the option to edit and reply with Word, Excel, and PowerPoint files from attachment previews in Outlook. Users will still be able to edit their files using web or desktop apps and then attach a copy or a link to the file in OneDrive to share it.
When this will happen:
Microsoft will start rolling out this change in late June 2023.
How this will affect your organization:
Users of this feature will now have to open the attachment using web or desktop apps and then download a copy or save the edited file to OneDrive before sharing it either as an attachment or a link.