When ever i try to connect to wifi, it says authentication problems. what does that mean?

This could be a dhcp issue, try using a fixed IP address when logging in.

try making it "forget" the wifi network, then restart it. then finnaly put the wifi password back in, see what happens.

If I am understanding the problem, then you are trying to connect to a network that is password protected (that is what the lock symbol generally means when shown beside a network that has been discovered by your device). It cannot 'authenticate' you until you key in the correct password. However, if that is the case, when you click/touch that network and then touch Connect, it should automatically pop up a box asking for the password. Key in the password (be sure to get upper/lower case correct on any letters), and then touch Connect. If that does not work, or if I misunderstood, then provide additional info and we can try again. Good luck!

You will get an 'authentication' problem trying to connect to this dlink 600 or any other wifi services/routers that are 'protected' and encrypted using WEP or WPA or WPA2 security (e.g. not public or 'OPEN' network): apart from the SSID, you will need to set your android tablet or ipad to use the WEP or WPA or WPA2 PASSWORD/PASS KEY to successfully connect (you get it from the Wifi/Router administrator).

trying dumbing down the authentication on your wifi router. Try these:
turn off 40mhz wide channels
try wpa instead of wpa2
try tkip instead of aes

if all else fails, try wep.

am having authentication problems with my irulu wifi tab

Can't get unit to connect to my home wifi , keeps giving message Authentication Problem

mine too! :( and i don't know how to fix it :( help!

The AP & DNS means a code which makes your mobile registered.the dns and ap address will be getted from the wifi connection center .