Q: I received a document that had been edited by another user. When I make additional edits, they show up as a different color and under my author name, but when I save the document, they change to the first author's color and author name. I've tried saving the .docx document to a .doc, but it didn't help. I'm running 2007.

A: Probably in Tools Options Security you have checked “Remove personal information from file properties on save”. Since the reviewers' names are considered personal information, they're removed and replaced by the anonymous “Author” – and of course there's only one Author, so all the colors collapse to
one.

Office 2016: File → Options → Trust Center → [Trust center settings…] → Privacy Options → uncheck [ ] Remove personal information from file properties on save

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