It was created in a newer version of InDesign. Ask whoever send you the document to export it as IDML, and send you that.
Are there any other options? The person who created it is no longer working with the person who sent it to me for editing.
If you are willing to share it via dropbox (or other file-sharing service), I can save out the IDML for you.
Yes, I'd be happy to VIA Dropbox. What's your email.