1. Try resetting the DNS Cache and restore the hosts file:
"Flush the DNS cache and restore MS's Hosts file ...
Copy and paste these lines in Note pad.
attrib -h -s -r hosts
echo 127.0.0.1 localhost>HOSTS
attrib +r +h +s hosts
netsh winsock reset all
netsh int ip reset all
shutdown -r -t 1
Save as flush.bat to your desktop. Right click on the flush.bat file to run it as Administrator. Your computer will reboot itself."
From Post #5: Detected DNS cache poisoning attack.
2. Reset and turn off the router for 5 minutes
3. Look into your Wireless Network Configuration.
4. Replace your Wireless Card
5. Call your ISP.