Configuration Backup (CFGBACK.EXE) Use this tool to create a backup copy of a computer's Registry files. For information, see CFGBACK.HLP. Configuration Backup backs up only the Registry. To back up other configuration files, such as CONFIG.SYS, use the Emergency Recovery Utility (ERU.EXE). For more information about backing up and restoring the Registry, see the main Registry topic in the Windows 95 Resource Kit.