AT&T GLOBAL DIALER

i am trying to connect to the internet via at&t global dialer. i connect to the server but when it tries to authenticate i get an error message the gatway could not send encryption key please try again. i have deleted the icon in dial up networking,didnt work, i have removed the ethernet card and all network components didnt work. i even reinstalled dial up networking didnt work. I am under the gun alittle because its for my CFO any help would be great