"This file can't be previewed because of an error in the Microsoft Word previewer."
- by danielson
The issue is:
Outlook 2013 simply will not give a preview of Word (nor Excel) docs in attachments.
Never had the issue with Outlook 2010. Using Outlook 2013 on Windows 7 64bit SSD with Word 2010.
I did notice that "Microsoft Word" is not listed specifically in Trust Center attachment handling, could that be part of the problem?
Excel, Visio, RTF and many more are there.
Update: strange, search can be performed in Word attachments... but can't preview Word file. So, Outlook can 'see' Word docs but won't let us have that preview.
For reference, here is a similar question I posted in the Microsoft Answers forum.