I had a netgear router that every device in the house worked fine with, but 2 out of 5 android devices didnt. I did a full factory reset and they started working but only for a month before they stopped. They would connect to the wireless but couldn't go any where online. Turned out to be a hardware problem with the way the wireless was done. Older wireless devices worked fine, newer had trouble.
Put in a new tp-link router and so far every single device in the house works fine.
First thing to do is to unplug the power on the router and wait 30 sec and plug it back in. Just like every single router I have ever worked with, they need rebooted every now and then. Such as the router not handing out IPs any more. A reboot fixes it. They are little computers after all.
Then if after a reboot it still isnt working then check for a firmware update for the router. A lot of times they fix bugs that have to do with new devices connecting to the wireless.
![wink :wink:](http://www.tweaking.com/forums/Smileys/smillhey/wink.png)
Shane