If you have received a message with an attachment which was created using Office 2007, you can preview it inside Outlook 2007 without having to open the file. As you don't have to wait for the application to open this is a much quicker way of peeking inside a file to view the contents.
To do so, select the message and right-click on the attachment. A menu will appear. Select 'Preview'.
The system will warn you that you should only open trusted content and also that in some circumstances preview may not show you the very latest version of the file. You can uncheck the 'Always warn before previewing this type of file' if you don't want to be constantly reminded of these risks. Click 'Preview file'.
Now, instead of the contents of the email the Preview window will display the contents of the file. In this case it is a simple Word document but it could be an Excel file or even a PowerPoint presentation. If previewing a Powerpoint file you can click on the previewed slide to move through the presentation.
To switch back to the email itself just click on the text 'Message' next to the little yellow envelope.