Wii Error Code 52500-52599 - Wii Error Codes

This error is caused by an issue with the Wii console being unable to connect to your proxy server, commonly found at office buildings and dormitories.

To solve this error :

Check proxy server settings for incorrect usernames, passwords, or settings.
Try changing the channel of your wireless router to either channel 1 or channel 11 which can increase download speeds. Be sure to test both channels to see which works better or faster.
A manual setup of internet connection settings for the Wii console may be necessary. For proxy server information, please contact your network administrator.