Turning off change tracking does not remove changes that have already been tracked. Instead, turning off change tracking enables you to modify the document without marking what has changed. To remove tracked changes, use commands on the Reviewing toolbar to review and accept or reject the changes.
On the Tools menu, click Track Changes.
When the Track Changes feature is enabled, TRK appears on the status bar. When you turn off change tracking, TRK is dimmed.
You can also double-click TRK on the status bar to turn change tracking on or off.
If the Track Changes command is unavailable, you may need to turn off document protection by clicking Unprotect Document on the Tools menu. (You may need to know the document password.)
If you turn off change tracking in a document and change tracking is turned on when you reopen the document, you may need to modify the file properties. On the File menu, click Properties, and then click the Custom tab. In the Properties box, click each item, click Delete, and then close the document. When you open the document again, change tracking is turned off.