Nintendo Network Identity Code (NNID)Your NNID is your user identity when you use the console. If you own a Nintendo 3DS console then you can use the same one for your Wii U.
What is a NNID?:
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Guidance on creating a new NNID:
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Guidance on using your existing 3DS NNID with your Wii U:
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Connecting the Wii U to your wi-fiThe console will usually be able to connect to your wireless hub as per any other computing device. If you experience difficulty then you may need to manually change the settings. Kotaku noted some setting information that may help you -
Link. If you'd prefer to use a wired ethernet connection then Nintendo supplies a branded adapter ("Wii LAN Adapter") that can be purchased -
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Gamepad wireless connectionThe Gamepad connects wirelessly with the Wii U console. Whether you can move around your room or home without the signal being affected will depend upon the type of walls that you have in your room. If the building is modern with thin (plasterboard) walls then the signal will go right through; but if the walls are traditional (brick or stone) then the connection will be impacted.
StorageThe Wii U console is supplied with either 8Gb or 32Gb of on-board storage; it refers to the space available for storing games and files on your console. As digital downloading is becoming increasingly popular, you may find that you want to have more storage space. The Wii U has USB connection ports which allow an external storage device to be plugged in.
Nintendo recommend that an externally-powered hard drive is used. Some owners have successfully used USB flash drives and hard drives that take their power from the console, but these are not recommended by Nintendo.
In general, most externally-powered (i.e. with its own power supply) USB (v2 or v3) hard drives can be used. The ports themselves are v2 but compatible with v3. The console supports drives up to 2Tb in size; a larger drive could be used but only 2Tb of space will be available to the console. Nintendo maintains a list of compatible drives that they have successfully tested with the console -
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Transferring your Wii console content to your Wii U consoleGames that you have stored on your Wii console can be transferred to your Wii U. If you transfer a Virtual Console game that is available (or later made available) in an enhanced Wii U format then you will be entitled to upgrade the game at a reduced cost to the eShop pricing.
Games that are transferred to your Wii U console are accessible via the "Wii mode" icon on the console's main menu.
Guidance on the Wii to Wii U transfer process -
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Controller compatibilityWii Remotes, Wii Remote Pluses, Nunchucks, Wii Classic controllers and Wii wheels are compatible with the Wii U console. The controllers need to be paired (connected) with the console before they can be used.
Nintendo information on playing styles:
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Linking up with FriendsPlaying online is a major feature of modern gaming and you can do this with your Wii U console. You can also communicate with your friends in fun and innovative ways - refer to the Miiverse section below.
Guidance on linking up with friends:
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The MiiverseThe Miiverse is the central communication hub of your Wii U console. It allows you to message, draw and communicate with your Wii U friends and other Wii U owners. The Miiverse also features specific areas ("communities") in which you can view and share information about specific games. You are able to write messages, post screenshots and, more recently for the Mario Kart 8 game, post video. Try looking around the Miiverse - it's amazing!
The Miiverse can be viewed via PC or tablet device but it is at its most effective when accessed via your Wii U console. The Miiverse can also be used through a Nintendo 3DS console, but it is slightly slower and not quite as fully-featured.
About the Miiverse:
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Miiverse - PC login:
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