Block CD/DVD writing in windows 7

Hi ,

SEPM  version 12.1.6 MP1

https://support.symantec.com/en_US/article.TECH104800.html

I followed the instructions in the above link to block  read and write to  CD /DVD in Windows 7 and does not work. I even rebooted my workstation and I can still acces the files from the DVD. I have Application and Device Control feature enabled as a part of client package and deployed successfuly. I even enabled the policy to deny read and write to USB which is working perfect.

Please let me know if I am missing anything here.

Thanks,