Hi all,
I was having this issue and tried each thing in this post with varying success. I am using New Outlook for Desktop in Windows 10. My desired settings are large text (Roomy), with single-line messages in inbox, and I do not like the preview pane. I want the single-line messages to remain that way regardless of the window size.
I was able to achieve this with the following settings:
> Gear Icon in top right corner of Outlook
> Settings > Mail > Layout
Focused Inbox: Don't Sort Messages
Text Size and Spacing: Large
Message height: greyed out, cannot select options.
Reading Pane: Hide reading pane
Message Preview text: Hide preview text
Inline attachment previews: Don't show attachments in message list
I believe the inline attachment previews has the greatest affect on single vs. multiple rows. This seems to be working for me.