"Prevent Copying" option in mail greyed out

A user just called and said that she could not select the Prevent Copying option under Delivery Options in a memo. I tried and I am getting the same thing. The option is greyed out and unselectable. How did it do this and how do I bring it back??

Subject: “Prevent Copying” option in mail greyed out

Hi Jake,

Just refresh/replace the mail file with the master template.

Hope this will resolve the issue.

with reg

Sethuraman Navakody