If you gto an erro message that you need to upgrade to CS7 you are either using CS6 as part of a clooud subscription, or you are not using the latest version of CC. CS7 does not exist as the decision was made to change the name to version CC, but it was made after some of the error dialogs were written. In eihter case, you need to download the latest version of CC through the cloud subscription.
This file was created with InDesign CC Version 9.x, which should be CS7 when CS6 was developed first.
But you should update your version anyway. With an updated version you will get a different message.
I believe that CS5.5 7.5.3 and CS6 display that message with a file created in CC 9.1 and 9.0. With 9.2 it will display that was created with CC 9.2.