A family of Microsoft word processing software products for creating web, email, and print documents.
Track changes has been turned on. Perhaps the author wants to know exactly what you change.
If you're certain that you don't want to keep track of changes to the document:
Activate the Review tab of the ribbon.
The "Track Changes" button should be highlighted. Click it to turn it off.
Next, click the lower part of the Accept button and select "Accept All Changes in Document".