Your firewall displays a message indicating that connections to the server of WOW have been blocked.
To remedy this, simply open the ports 3724 and 6112 on your firewall.
The following pages describe the configuration of the most popular firewall:
If you have a router, it can also act as firewall. The next page describes the configuration of the commmonly used routers: (Belkin F5D5231, D-Link DI-604, D-Link DI-624, D-Link DI-784, Linksys BEFSR41, Linksys BEFSR41,SMC 7004ABR, Netgear FM114P, Netgear FR114P, Netgear FR114W, Netgear RP114):