DECS has switched Engineering's authentication system to Kerberos. This change in Engineering's authentication system was necessary to implement newer standards. As a result of the change, all Engineering users were required to visit the new "My Account" website to review/change their password. The change was phased in over time which provided Engineering users with ample opportunity to update passwords.
For further directions on how to change your password, see the How-to called DECS Password Authentication Instructions.