How to link a GPO to an OU?
- Logon to the domain controller as an administrator.
- Start → Administrative tools → Group policy management console.
- Navigate to the desired OU, to which you want to link a GPO.
- Right click on this OU and select "Link an existing GPO" .
- In the "Select GPO" dialog under Group Policy Objects, select the GPO you want to link and click OK.