How to hide the preview panel?

How do you hide the message preview pane? I don’t want to see the contents of every e-mail in my inbox when I highlight one. I’d rather not have a preview pane at all.

Settings > Appearance > Layout

Thank you. I figured it was simple, but I don’t have it and my customer has been bugged by it.

I just started using eM Client and I am having trouble finding the settings to make this change.

Menu > Settings > Appearance > Layout > Layout > Messages panel off