I'm fairly new to using a Mac and trying to revise a paper with a colleague.

I've tried the following 2 ways to insert a comment on the DocX and have been unsuccesful...

1. Clicked "View"; scroll to "Toolbars"; clicked "Reviewing"

2. Clicked "Insert" - the "Comment" option was gray and could not be highlighted.

I tried multiple things (highlighted an item; clicked the cursor at a particular point in the document) before attempting both options and have been unsuccesful.

Any ideas? Is it possible that the original author locked the document from receiving comments? Thanks in advance.