Making the preview pane display
Resolution
In Yahoo! Mail, the preview window does not display by default. You can easily change this setting, though, if you prefer to have the ability to preview emails before you open them. To do so:
- In the toolbar at the top of your message list, click Actions | Enable Preview Pane.

- A pop-up appears, saying that Yahoo! Mail must refresh in order to switch view. Click OK.
Additional Information
- You can adjust the size of the preview pane. For more information, see How to adjust the size of the preview pane.