Imagine that you've asked someone to review a document, but you forgot to turn on Track Changes first. Have you forever lost the chance to see where changes were made and systematically resolve them? Not necessarily.
If you have a copy of the document in its original form (before the reviewer edited it), you can use Word's Compare and Merge Documents feature. When you're finished, you have a document that includes change marks wherever additions, deletions, and, optionally, formatting changes were made—just as if the edits were made with Track Changes enabled. Follow these steps:
Open the document where you want the change marks to appear.
Choose Tools, Compare and Merge Documents. The Compare ...