If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

Microsoft is trumpeting support for its Office Open XML document file format as an international standard from more than 300 companies and organizations on a new "community" Web site set up by the ...

The next version of Office will fully support two new file formats, Strict Open XML and Open Document Format 1.2, Microsoft has announced. In a blog post on Monday, Office standards chief Jim ...

The introduction of Office 2007 brought a wave of document compatibility issues for users of Office 2004, but Microsoft has at last delivered a non-beta version of its Open XML File Format ...

The royalty-free license under which Microsoft Corp. plans to make its upcoming Office Open XML Formats widely available is incompatible with the GNU General Public License.

Citing statements of support from more than 300 companies and organizations, Microsoft claimed on Tuesday that interest in its Office Open XML file format continues to grow. Comments backing the ...