Alright, so I got a black Mario Kart Wii system bundle for christmas. I am able to connect to the internet perfectly fine (I even was able to download a game from the shop channel.) However, whenever I go to play Mario Kart Wii online, or ANY game for that matter, I get the error code 20100. Basically it says either the Wi-Fi network could be down, or its a router problem. However, we also have a white Wii, and that system CAN play any game online without any problems (I did a side-by-side comparison.). I have already done the connection test multiple times, and it says that I'm conneted to the internet, so I'm not sure what to do here...
make sure the channel is set to 1 or 11.
Channel on what? And shouldn't it already be on that channel if it works on the other Wii?
It sounds like it might be a temporary WiFi issue on Nintendo's end. There tends to be a lot of those around the holidays. If it has been a few days, and you're still having trouble, try adjusting your router's broadcasting channel to 1 or 11, as that is what tends to work best on the Wii. If that doesn't work, try erasing all of the Wii's internet connection settings and start from scratch again; that might work.
Been getting the same thing as well for over a week. Have had the Wii for a year and was working fine until last week. Then, error 20100 out of nowhere. Netflix and Mario Kart no longer work online. However, I can still connect to the weather channel, the internet channel, and the wii shop channel fine. Have tried changing every single option available on my router, with no luck. This is extremely frustrating. Any other ideas?