Itqualityassurance
Why is my restrict editing greyed out?
When the enforcing protection option appears gray and can't be clicked, it isn't available. Usually the reason that it doesn't work is because another type of protection is already in place on the document. Changing the status of the document will make the option available again.
How do I unlock a locked document for editing?
To resolve this issue, first confirm that another user on the network does not have the document open. If the document is in use, open the document as read-only. If it is not in use, quit all instances of Word, and then remove the owner file.
