• click on Tools->Settings as follows:

• Enter your user password if prompted.

The Settings page will appear.

• Click on "Client Settings->Security" to bring the screen below:

• Click on Website Restriction

The Website Restriction page will appear.

• Click "Turn ON Website Restriction"
• Enter the website's window title in the textbox. Wildcard "*" character can be used.
• Click Add.
• Select the client stations to block websites. 

The website's title you specified will add to the Restricted Sites list.

In the below example, *hacking* is added. This will block all sites with *hacking*
in the title in client stations PC 002 and PC 003. Wildcard "*" represents any
character or words with any length.