Can not preview message in Mail.app Using last OS X Lion, I was using Mail.app, classic view, so there was always a preview for each message. This has now dissapeared, how can I solve this?
Classic view is the view set in Preferences>Viewing>Use classic layout:



In this view, the message preview area is located below the message list. 

The view may be minimized:



Just drag the separator at the bottom of the window to show the message area.