Apparently the ds and ds lite cannot access wpa2 networks either use wpa or unprotected wifi you wont be able to connect to multiplayer games for that go look up a guide for that and for. You can use this to play nintendo ds lite games online that have been especially designed for nintendo wi fi connection.

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Nintendo ds lite connect to wifi. Tap one of the connection save. This utility program will configure the nintendo ds to. For detailed directions consult the. In order to use the nintendo wi fi usb connector the pc must use windows xp at least service pack 2 and have an active broadband internet connection. The nintendo dsi and nintendo dsi xl must be configured to use connection slots 1 2 or 3 during the set up process in order to play online multiplayer games. On the nintendo wi fi connection setup screen tap the nintendo wi fi connection settings box.
Nintendo wi fi connection nintendo ds and nintendo ds lite. Have a question about the nintendo wi fi connection including wireless security profile management routers and more. With an online capable game inserted into your nintendo ds turn on your system and access the games main menu. The nintendo wi fi usb connector enables you to connect the nintendo ds lite to the internet via a pc. These settings are typically found by selecting nintendo wfc from the games main menu. Do not use the advanced.
For nintendo ds on the ds a gamefaqs message board topic titled trying to connect my ds lite to wifi. The setup utility program is included in all nintendo wfc compatible nintendo ds games. Access the nintendo wi fi connection settings.