J´ai essayé ton lien et ça a marché chez moi (le site), voilà ce qu´ils disent :
There appears to be an issue with your wireless router´s firewall.
Try a "Manual Setup" with the Wii console (how to), using your network´s DNS information. To access the DNS settings:
On your PC, click "Start" and then "Run."
Type "CMD" into the field that appears to open a new window.
Type "IPCONFIG/ALL" and press "Enter" to display a list of internet settings, including the "DNS" settings. Input these into the "Manual Setup" of the Wii console´s internet connection.
Review the information on our Firewall/Antivirus/Antispyware/Adware compatibility information by clicking here. This page offers many tips and recommendations to get your connection working through a firewall and other security programs that can be blocking the Wii console´s online connection.
If you are still receiving this error code, please click here for assistance.
Donc en gros c´est soit le DNS (ce qui n´est pas mon cas vu que j´ai pu dl la MAJ) soit le parefeu.