Microsoft has rebuilt its host of Office applications from the ground up. Along with the bold interface changes and new features in Office 2007, revamped file formats will affect how you work in Word, Excel and PowerPoint, regardless of whether you plan to upgrade to Office 2007 from an earlier version.
If you're using the 2000 through 2003 versions of Office, you'll be able to open the new Office files after you follow Microsoft's prompts to install compatibility updates. You'll also be able to open older Office files within the new Office 2007 applications, although some of the new features won't work until you save the older file in the most recent format.
The 2007 file formats for Microsoft Office software are Open XML-based, so they compress more information into fewer kilobytes and thus require less hard drive space than their predecessors. An added X marks the extensions of these new files; for instance, the DOC extension from Microsoft Word will be DOCX in Word 2007, Excel's XLS becomes XLSX, and so on. Other Office 2007 file extensions include DOCM, for Word documents that enable macros. The Open XML format, also known as OOXML, will be open source. However, Office 2007 software will not let you save work in either the Open Document Format used by OpenOffice or in the formats from Corel WordPerfect.
If you plan to share Office 2007 files with people who use older versions of Microsoft Office or rival Office software, the following pages tell you what you need to know (you can also view our video to walk through these steps).
Saving backward-compatible files within Office 2007
When you select Save within Word, Excel or PowerPoint 2007, your file will be saved in a new Open XML format by default. A Microsoft Word 2007 file, for instance, will have the DOCX extension. Luckily, Microsoft Office 2000 and 2003 can open the new file formats after you install a Compatibility Pack update (see the next page). However, Office applications that preceded version 2000 won't open Office 2007 files at all, nor will most third-party productivity software that opens older Microsoft files. What if you need to share that DOCX file with someone running an older version of Word? Or what if you use a third-party application, such as Corel WordPerfect 12 or the Web-based Google Docs, that can only read Word's older DOC format?
The Microsoft Office button in the upper left corner of the 2007 applications lets you check for file compatibility and save backward-compatible versions of your work. The best bet for making files from Office 2007 compatible with older (or rival) Office software is to save your work in an older file format. This is especially true while Office 2007 is new, because the majority of Office users aren't likely to upgrade immediately, so they'll continue to use the older software and file formats.
To save backward-compatible work using Word, Excel or PowerPoint 2007, make sure to click the Office button and choose Save As — not Save — from the pull-down menu. Then you can choose to save work in the DOC file format that older versions (from 1997 to 2003) of Microsoft Word can open.
Before you save a file, it's also a good idea to select Prepare from the Office button and run a Compatibility Checker. This process will show how the file might change when it's opened in earlier versions of Office.
Opening Office 2007 files in older Office versions
If you use Microsoft Office editions 2000 through 2003 and aren't ready to upgrade, you should be able to open work that someone else saved in the new, 2007 formats. However, this process isn't seamless. First, you must take steps to allow the older software to read the newer file.
The Compatibility Pack download that makes this possible requires that you run Word, Excel and PowerPoint 2000 or 2002 with Service Pack 3 or run the 2003 editions of those applications with SP1 or higher. Your operating system must be Windows 2000 SP4, Windows Server 2003 or Windows XP with SP1 or newer.
If you're running older Office software that meets these requirements, you should receive a one-time prompt to download the Compatibility Pack when you try to open a 2007 Office file. However, without the latest software updates, the Compatibility Pack may not fully work.
If you try to open an Office 2007 file with Office 2003 or 2000 but aren't prompted to install a Compatibility Pack, then you probably need to update your older Office software first, by visiting update.microsoft.com. When that's done, you can restart your machine and get the Compatibility Pack at download.microsoft.com.
After you've installed the Compatibility Pack, you must restart your computer for the changes to take effect. With that done, you should be able to open Office 2007 files with older Office software. If you open an Office 2007 file in Office 2003, choosing Save will keep that file in the new format. The same is true for Word 2000. In Excel and PowerPoint 2000, however, you must choose Save As to keep an Office 2007 file from reverting to an earlier format.
Working in the Compatibility Mode of Office 2007
When Office 2007 opens older Office files, the software shuts off some dynamic features that aren't available in the older software. The Ribbon toolbar within Word, Excel and PowerPoint 2007 looks different when the software runs in Compatibility Mode and some of the features are disabled.
When you're editing a Word 2007 DOCX file with Word 2007, for example, you'll get all of the new features, such as those for applying styles and shapes to an image. But if you open an older, DOC file, Word 2007 runs in Compatibility Mode. The galleries of styles and shapes from Office 2007 are gone, although you can still adjust the image in other ways.
If you'd like to use all of the features available within Office 2007, you can convert a file from the older type to the new, Open XML format. To do that, click the Microsoft Office button in the upper left corner of the interface and select Convert. Compatibility Mode ends.
If you created a file using an Office 2007 application, later saved that work in an older format to use in Office 2003 or 2000, and then converted the file back to the 2007 format, all of the original elements from the 2007 version should remain intact.
There are many options for opening, editing and saving work in several versions of Microsoft Office. Nevertheless, we expect the steps required to deal with the new file formats outside of Office 2007 will trigger some headaches.
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