The boot loader, once executed, searches for a Windows operating system. Windows Boot Manager does so by reading Boot Configuration Data (BCD), a complex firmware-independent database for boot-time configuration data. Its predecessor, codice_5, does so by reading the simpler codice_28. If the boot.ini file is missing, the boot loader will attempt to locate information from the standard installation directory. For Windows NT and 2000 machines, it will attempt to boot from codice_29. For Windows XP and 2003 machines, it will boot from codice_30.