Tweaking your WiFi configuration for maximum throughput sometimes have adverse side-effects, we have already seen how changing your WiFi channels can create problems with non-standard or incompatible WiFi cards.

Having customized your WiFi config can also create strange problems like WiFi being visible and connectable but with limited functionality and no web-browsing. As evident from the screenshots on the right and below my iMac running Mac OS X 10.8.2 is having issue communicating with my router, after researching over the internet reading numerous forums and help articles I finally figured out the solution experimenting with my router config.

Imagine the confusion when your WiFi network is showing all available WiFi access points in the neighborhood except the one you want to connect to, adding more confusion - the same access-point is visible and connectable from other devices. Since, your WiFi access-point is visible from other devices and your WiFi client can see other access-point we can be sure that the two particular devices are working fine and are only having issues communicating to each other.