Quick Fix: When a new device won't connect to a router that you know is
working the first thing you want to check is make sure there isn’t a
problem with the device. Check to make sure you can connect the device
to another network, maybe a wireless hotspot. If the problem remains,
check to make sure your device is connecting to the right wireless
signal on your router, if you have a dual-band router.
Dual-band routers transmit signals at two bands: 2.4 GHz and 5 GHz. Some routers will use the same SSID for each band and then some devices can connect automatically to the correct band. Almost all tablets, e-readers, gaming systems, and so on can connect to the 2.4 GHz band. Some newer wireless devices can connect to 5 GHz.
Whenever I set up a router, I like to make sure I create different SSIDs for the 2.4 and 5 GHz bands. This way I can control which device connects to which band. For example, if I set up a Linksys dual-band router, I can name the 2.4 GHz band "Linksys_24" and the 5 GHz band "Linksys_5."
It's important to know at which band specific devices can connect. For instance, the iPhone 4S only supports the 2.4 GHz band. Motorola's Droid Razr, the non-LTE version, support both 2.4 and 5 GHz.
To see a listing of Wi-Fi support for the hottest wireless devices, check out The Wi-Fi You Need for the Gadgets You Want. If you don't see your device listed, or are not sure about the wireless compatibility, contact the device's manufacturer.
Internet Connection Tips; I can't connect my new wireless gadget to my router.