Do one of the following:
Protect with comments and changes
To let reviewers change the document by inserting comments and tracked changes, click Tracked changes.
To let reviewers only insert comments, click Comments.
To let only authorized reviewers unprotect the document, type a password in the Password box.
Unprotect for comments and changes
On the Tools menu, click Unprotect document.
Note If you used a password to protect the document, you'll need to enter the password before you can unprotect it.