How to Enable the Check box "Allow inheritable permissions from parent to propagate to this object" on all Users

I have to enable the Check Box in Active Directory 2008 R2,  "Allow inheritable permissions from parent to propagate to this object" on all Users of about 300.

We have about 50 OUs.

I try to apply the Scripts Mentioned here:

http://social.technet.microsoft.com/Forums/windowsserver/en-US/db378974-9cbf-4712-9978-f6a1a5234c16/allow-inheritable-permissions-from-parent-to-propagate-checkbox

It not seems to work.

What is the Exact way to apply these scripts in 2008 r2.

is there Program to achieve this goal?