When you save a file, the program you’re using saves it in a particular format. The format describes the way the various elements of the file are stored. For example, let’s say you write something in a word processor. Maybe you boldface some text, or change the margins, or add a picture. Different word processors will store that information in different ways when the file is saved.

Unfortunately, different programs use different formats for the same types of files. Wordperfect uses a different file format from Microsoft Word. So a file saved in one of these programs won’t necessarily be readable by the other one. More confusingly, Microsoft Works also uses a different format from Microsoft Word, and different versions of Microsoft Word use different formats.

This used to be a huge problem. Our school computers had MS Word on them, but people had documents they had created in MS Works, or ClarisWorks, or a different version of MS Word. It was a pain to try to open these files or convert them from one format to another. We used to recommend that people use the “rich text format” (rtf) when saving word processing files. Rtf files can be opened by just about any word processor, and they retain the basic formatting for the document. That’s still a pretty good idea if you need to access your files on multiple computers running different software, or if you’re sending a document to someone and you don’t know which word processor they use.

Things got better in the early part of this decade. Microsoft used the same file formats for its Office products from 1997 – 2006. So even if you had Office 2003 at home, a file saved on that computer would open just fine on a computer running Office 2000, or even Office 97. We didn’t have to worry about it anymore.

That changed with Office 2007. If you create a document in Word (or Excel, PowerPoint, etc) 2007, you can’t open that file in an older version of the program. The two use different formats, and the older program doesn’t know how to handle the newer one’s files. Fortunately, there are two ways to work around this.

On the computer with the newer software, you can save the document in an older format. When you go to the Save As dialog, you can select a file type. In my version of Word, it’s right below the filename. Simply pick the format you need for the computer you’re going to use, and save the file. For example, in my district, if you save it as a Word 2000 file, you’ll be able to open it on any computer in the district.

The other thing you can do is to install a compatibility pack on the computer with the older version of Office. Available from Microsoft, the compatibility pack allows older versions of Office to read the new document formats.After downloading the software, double click on the installer and accept the license agreement. When it’s done installing, you’ll receive a message saying that the installation is complete. Simply click on “OK,” and you’re done.

Now, you can start one of your Office programs and try to open a file. In the file types drop-down, you’ll now see the Office 2007 file formats listed. You can then open these files and use them in the older version of Office.