Q: Somebody just emailed me a “docx” file. Is this a Microsoft Word file? Why can’t my copy of Word open it?
A: You’ve received a document created in Microsoft Office 2007. The “x” at the end of the usual “doc” file-name extension means it was saved in one of Office 2007′s new, more efficient file formats, which older Offices releases can’t read without a free update from Microsoft. To get this add-on, go to microsoft.com/office and type “Microsoft Office Compatibility Pack” in the search form. Downloading and installing it will enable Office 200, XP and 2003 to read and write the 2007 formats. If you use Mac, Microsoft’s just shipped Office 2008 supports the new formats, and a free file converter for Office v.x and 2004 is available at microsoft.com/mac/downloads. Apple’s $79 iWork ’08 can read, but not write, these files. office 2007 users can avoid compatibility problems by telling Office to stick the older formats. In Word. Excel and Powerpoint, click the round Office button at the top-left corner of the window, then click the Options button in the drop down menu that will appear. Now click the Save category at the left of the Option window. In the “Save files in this format” menu, choose the previous format for each program: Word 97-2003 Document (*doc), “Excel 97-2003 Wordbook” and Powerpoint Presentation 97-2003.”
Source: Rob Pegoraro attempts to untangle computing conundrums and errant electronics each week. He writes for the Washington Post “Fast forward help file”. Send all email firstname.lastname@example.org