If you're using Word 2007 or above, go to Review tab, click New Comment and select Unrestricted Access from Protect Document.
In Word 2003 or below, click Comments from the Insert menu and select Stop Protection from Protect Document window.
In both cases, if you receive an Unprotect Document dialog box, it means that the file is password-protected and you will need to know the password in order to unlock it.
