When ATE (actually ashw32.exe) is launched, it looks for ATESTART.CMD[2,2] or ATESTART.DO[2,2] and if found, executes it. Otherwise, it executes TELNET <config> to initiate the connection. The ATESTART (CMD or DO) file allows you to fine-tune the configuration of the ATE client prior to connecting to the server—perhaps to customize the menus, for example. The more common way to customize the ATE environment would be from the server side after the connection has been established, typically using the Extended TAB(-10,x) Commands.