To stop SafeDNS filtering, you should return the network settings on your computer to the original settings provided by ISP or your network administrator.
If you have installed the SafeDNS Agent you need to uninstall it. After that, your network settings will be automatically restored to the initial settings.
In order to manually change your DNS server address in Windows OS to the original one, open the network settings dialog box and either tick 'Obtain DNS server address automatically' if your ISP supports it or insert DNS addresses provided by your ISP.
You can also use instructions provided by Microsoft.