If you are still having problems, try adding this to your GW2 Shortcut Target:
-assetsrv 62.154.232.187:80
Here is a list of alternatives to also try:
194.25.94.170:80
174.35.71.9:80
151.249.90.199:80
93.188.135.37:80
62.154.232.194:80
You can do this by right clicking on your GW2 Shortcut and adding the above text to your Target field. For example your target should look like this:
“C:Program Files (x86)Guild Wars 2Gw2.exe” -assetsrv 62.154.232.187:80
put your DNS 8.8.8.8 8.8.4.4 (this is what standard "gamer" use.) and cmd ipcofing /flushdns
or you can waste your time like user/k0tten.