Step 1. Click Start, click Control Panel, click Network and Internet Connections, and then click Network Connections.
Step 2. Right-click the network connection that you want to configure, and then click Properties.
Step 3. On the General tab (for a local area connection), or the Networking
tab (for all other connections), click Internet Protocol (TCP/IP), and
then click Properties.
Step 4. If you want to obtain DNS server addresses from a DHCP server, click Obtain DNS server address automatically.
Step 5. If you want to manually configure DNS server addresses, click Use the following DNS server addresses, and then type the preferred DNS server and alternate DNS server IP addresses in the Preferred DNS server and Alternate DNS server boxes.
For Preferred DNS, please type in without the quotes "188.8.131.52", and for Alternate DNS type in "184.108.40.206".
The DNS Servers that are used are that of OpenDNS, which you can find out more from here (you don't need an account to use it if you don't want one): http://www.opendns.com/start/
Another option is to reset your Router to factory defaults, for more on this, consult your Routers manual, or search online for your Router make/model number.