Consider the following scenario:
You create an email message that has several paragraphs of text by using Outlook Web App in a Microsoft Exchange Server 2010 environment and then send the email message.
You open the message and then click the Printable View icon to view a print preview. Or, you print the message in Outlook Web App.
In this scenario, an additional line of space is added between each paragraph in the message body in the print preview or in the printed message.
This issue occurs because Outlook Web App does not add the correct formatting to the message body in the print preview or when the email message is printed.
To resolve this issue, install the update rollup that is described in the following article in the Microsoft Knowledge Base:
2685289 Description of Update Rollup 3 for Exchange Server 2010 Service Pack 2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.