New Outlook Offline Mode: Add and open attachments while offline

Microsoft has been rolling out offline functionality in phases, and the latest update now allows users to add and open attachments while offline.

I created a short walkthrough covering what works offline now, what users need to know about attaching files from OneDrive versus local drives, and which features still require an internet connection.

I also shared my discoveries when creating a calendar event that you don't want to miss. 

Video: https://www.youtube.com/watch?v=SYsraZBTack

traccreations4e-p26 6/15/2026