Maybe try View-Layout-Vertical from the menu bar.

No menu bar? Press the alt key.

queenofpersia said

i want to change the layout of my email messages so that the message is at the side of the headers not below them. i have just downloaded mozilla thunderbird on to my new laptop at i cant get the layout that I prefer back. please help . thanks june

thank you so much Airmail. I had been told this was the way to do it but couldnt find the menu bar, but now I have. thank you so much for your help, so simple and yet it has made my day! best wishes june