I have this problem - when I turn on my PC, and also later at random, I get an error message about not being able to connect to the DNS server. It sometimes helps if i type ipconfig /flushdns, however just temporarily. I am using my ISP's DNS server. After contacting them, they gave me another address, yet the problem still persists. They say that they see no problem at their end? What could be possibly causing this problem?