Nintendo is apparently experiencing some "technical difficulties" with its online services for the Wii U and 3DS. Attempting to access the Wii U eShop or many of the systems' other online services are resulting in various error codes.
Specifically on the company's online service status page, Nintendo confirms the Wii U's online services are "experiencing technical difficulties." The 3DS meanwhile is experiencing technical difficulties with "some parts of the online services."
Let us know if you are experiencing any problems with the Wii U or 3DS and post your error codes in the comments below.