My daughter uses a router to connect her PC and laptop to AT&T's telephone network.
She recently tried changing her password and since has been down. She has talked to AT&T and Lynksys for hours with each
blaming the other guy for the problems. Can anyone point me in a direction of how to reset/reload the systems to get running again?
I believe AT&T uses Yahoo home page which has it's own password system.

Are you talking about the router password (to logon to the router) or the system password?