sitecom range extender cant connect to the internet

hi...i buy one sitecom range extender i configure it for the first time,i connect it to a unsecured acces point,at first it works fine but after 3hours or more the connection lost..then what ever i did i cannot connect to the internet..im trying now for 5days..i try to reset the range extender to do it from the start but it always failed..i can connect to the extender but i cannot access to the internet..it always "local connectivity or local access only"...can someone help me to my problem? thanks a lot..:4-dontkno