I've been using Office 2007 for a couple of months now and have not been able
to resolve an issue with the opening .xlsx files. The only way I can open
files in the new format (whether they are files I have created myself or
files that others have sent to me) is to first launch Excel 2007, then use
file/open and navigate to a location where I have stored the file. I cannot
open files by double-clicking or by using right-click/Open with.

I can open files in the old .XLS format by double-clicking them without any
trouble, and I can open new Word 2007 (.docx) and PowerPoint 2007 (.pptx) by
double-clicking, but not .xlsx files.

I've tried doing an Office 2007 reinstall/repair, but to no avail.

Any ideas?
--
Paul B