You may see an upgrade notification message similar to the one below when you attempt to open an iWork document (a file created in Keynote, Pages, or Numbers). This message may occur when: The file you're trying to open was created using a newer version of the iWork application than the one installed on your Mac. You have more than one version of iWork installed on your Mac, and your file is defaulted to open up in an older version of the iWork application.
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