Note: This article is written several years ago, and is no longer applicable today. Instead, visit iCloud.com or CloudConverter to convert iWork documents into alternative formats. Opinions expressed here are solely my own.

Original Article

If you are running OS X Mavericks, and you need to exchange iWork (Pages, Numbers and Keynote) documents with your friends, you have probably encountered this alert.

The alert says: “You need newer versions of OS X and [iWork app] to open this document.”

One way to open the file is to re-save them on a Mac that runs OS X Yosemite. This can be done through choosing File > Advanced > Change File Type and select the type as “Package” format, rather than “Single File” format in Yosemite. But sometimes, this workaround just wouldn’t be feasible. Luckily, there is a way.

First, right click the incompatible file, click “Get Info”. Change the extension from “.key” to “.zip”.

Then double click to uncompress the file.

It would look like somthing similar to this, consisting of three folders and a few thumbnails.

The next step requires packaging the Index folder without compression. The easiest way is to use BetterZip.

Simply open BetterZip. It will automatically present a new, empty view. Drag the Index folder into the view. It would look something like this.

Then hit save. If the advanced options do not reveal itself, hit the downward arrow to unveil them. Go to “Compression”, and change it from “Normal” to “No compression”.

Hit save. You’ll get something like this.

Trash the “Index” folder, but leave the “Index.zip” there.

Go back to the expanded folder. Right click on it, click “Get Info”, and add “.key” at the end of its name if it is a Keynote file, “.pages” if it is a Pages file, “.numbers” if it is a Numbers file. It would look like this:

Close the “Get Info” window.

Double click your manually-converted iWork document. It should open and work properly now.