I have a document management program that I use that will only save based on
file types. In order for other people who have older versions of Office to
be able to work with a file I save, I need to identify the old file
extension. (Yes, I know I can save to an xls file in Office 2007, but that is
not the issues here.) The program gives me a choice of file extensions such
as *.xlsx and *.docx and *.pdf.

Prior to installing Office 2007, it gave me the option of saving to *.doc
and *.xls. It does not do so anymore. I found out that if one also has an
old version of office on the machine, the document management program will
recognize *.doc and *.xls extension.

There seems to be some sort of a registry or similar issue here. Anyone
know how to solve this?