Hello, folks!
I decided answer this question because many people has this problem and they cannot solve it.
Firstly, I would like to apologize for any grammatical error because English is not my native language.
So, YES! Wii work with WPA2-PSK encryption. However, only with WPA2-PSK AES. TKIP isn't supported.
The problem is that very people indicate troubles for connect internet with this encryption and WPA and WEP too.
Normally this is caused for characters differents of letters and numbers in your wifi's password. If you use a password like "jean#12345" or "pierre_27" or "gonZAles-33" you may have problem.
Why some users no have troubles? Because they don't use special characteres or they use Wii in English.
YES!!!! If you use your Wii in French or Spanish, the special characteres work wrong and your password's connection will fail.
To solve this, set your internet conection working at English and then return to your preferred idiom.
If this tip do not work, try remove special chararacters from your wifi's password.
Good Luke.
