expiration date on published file

Exactly - we are well aware of this issue. The last CD they released like this was "protected" with Secure Pack, but when I changed the date on my PC, I was able to view the files (they were packaged in PowerPoint). Is there software we can purchase that will prevent this? I saw some previous posts on PC Guard for Lectora, but will the user still be able to access the files if they change the date on their PC?Exactly - we are well aware of this issue. The last CD they released like this was "protected" with Secure Pack, but when I changed the date on my PC, I was able to view the files (they were packaged in PowerPoint). Is there software we can purchase that will prevent this? I saw some previous posts on PC Guard for Lectora, but will the user still be able to access the files if they change the date on their PC?