Issue: Outlook 2013: How to Disable or Expand Message Preview. (Changed the message preview single line in outlook 2013).
1. Launch Outlook 2013.
2. Switch to the View tab at the top of the window to continue.
3. In the View tab, find the Message Preview option and click on it to expand the menu. By default, this option is set to 1 Line which means one line of the email can be seen without opening it. If you would like to disable this feature, choose Off. If you want to preview more content of the email, choose either 2 Lines or 3 Lines option.
4. Outlook will ask whether you want to apply the change to the current folder or all mailboxes. Just choose the one you wish and then the process will begin.
5. When the process is completed, you will notice that the preview line is altered.
As an example, below are the screenshots of how the emails look like before and after disabling the message preview.
Later, if you decide to switch or change the setting, just repeat the above steps and choose another option in the Message Preview setting.