Not all is there but I've made a sticky containing a lot of it at
Be sure the router is within 20 feet of first setup and NEVER HIDE the SSID. There are other reasons such as found at http://forums.cnet.com/7723-13973_102-560420/wifi-disconnects-from-time-to-time-galaxy-tab-7-plus/?tag=contentBody;threadListing
Why Samsung can't help is it is not their network. Some folk have a rough time understanding that.
We recently changed the network password for our home network, (note the encryption and security stayed otherwise the same) and our tv (PN60E7000FF) now fails to detect the network. We tried contacting Samsung but received no response, has anyone else had this issue or solved it?