Inspiron E1505 laptop Windows xp - can't connect to internet thru wireless network

Other computers on home network can. There is a yellow ! on everything in Network Adapter directory. I have disabled and enabled, uninstalled and installed these devices and downloaded drivers for: 1)Chipset 2) network Interface card - 3 files 3) wireless network card and 4)Dell wireless mobile bradband cards under Communication., Still no connection so no access to internet.