Compatibility Pack for Office 2007 File Formats
Most of you probably knows, but this article is for those who haven’t heard about Compability Pack yet. Together with Office 2007 new Office formats has been added to the Word 2007, Excel 2007 and PowerPoint 2007. Default file format has been changed from doc to docx, xls to xlsx and ppt to pptx.
Unfortunately you cant open these files with earlier versions of office. For those who doesn’t use office 2007 but deals with docx (or xlsx, pptx) files, Microsoft has developed a Compability Pack.
Compability Pack can be downloaded from Microsoft download center. Right after installation you will need to restart your pc. Then you can open, edit, and save Office Word 2007 documents in previous versions of Microsoft Office.
Before installing Compatibility Pack, make sure that you have all updates installed for your Office version.

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