Microsoft released a security update KB969604 for Office 2007 (around June 2009)
This update causes document variables within Word docx files to be scrambled.
This update might still be pushed out via Office 2007 updates
DO NOT save files as docx using MS OFFICE 2007 until you apply the MS hotfix # 970942 available here

If you are using Windows XP with Office 2003 or Office 2000 and have installed an older Office 2007 compatibility pack, documents saved as docx may also cause the scrambled document variables. Installing the 2007 compatibility pack published on 1/6/2010 (version 4) will prevent the document variables from becoming corrupt.

Those on Windows 2000 may not be able to install the latest compatibility pack, or the compatibility pack may not function properly. This situation will hopefully be rectified in the coming months.

What is a document variable?
Document variables store data inside the document, invisible to the user. The Tutor software uses them when converting the document to HTML and when creating the flowchart, just to name a couple of uses.

How will you know if a document's variables are scrambled?
The difficulty in diagnosing the issue is that the symptoms can take myriad forms. There isn't a single error message or a single feature that one can point to and say, "test for the problem by doing this." The best clue about the error is seeing any kind of string in an error message that has garbage characters, question marks, xml code snippets, or just nonsense. Such as "Language ?????????????xlr;lwlerkjl could not be found." It is also possible to see the corrupted data in the footers of the Word docs. And, just because the footers look correct does not mean that the document variables are not corrupted. The corruption problem does not occur in every document variable in the document, just some of them. Often it is less than a quarter of them.

What is the difference between docx files and doc files?
Office 2007 uses Office Open XML formats with .docx and .docm filename extensions.
- Docx is an Office Open XML word document.
- Docm is a macro enabled Office Open XML document.
This means the file structure behind the scenes is quite different from the binary file formats used prior to Office 2007 such as .doc, .dot, .xls, and .ppt.

Solution Summary:
For Windows XP and Word 2007: Install the hotfix, or save files as *.doc
For Windows XP and Word 2000 and 2003: Install the latest compatibility pack or save files as *.doc
For Windows 2000 with Word 2000 or 2003, do not use any compatibility pack, save files as *.doc

Emily Chorba
Principle Product Manager for Oracle Tutor