Dajadues, if you read the thread you will see this affects a lot of users, and it due to a disagreement between two ISP -- TeliaSonera and Cogent.  DAZ is on the Cogent network, part of which is no longer connected (de-peered).  It even stops some sites in US to reach other sites in US...

The ISP TeliaSonera is not blocking DAZ, but Cogent is not allowing TeliaSonera through anymore (and vice versa, so all European WoW servers are cut off from anyone connecting through Cogent, for instance), thus cutting a lot of people of from DAZ.  It is neither cookies nor internet history affecting it.