Acer Aspire One Series Generic User Manual page 23

The Create Factory Default Backup dialog box opens. This dialog box tells you the
estimated size of the backup file on your USB flash drive.
3 Plug in the USB disk, then click Start. You will be shown the backup progress
on the screen.
4 Unplug the USB flash drive and mark it with a permanent marker.
Important: Write a unique, descriptive label on each backup, such
as 'Windows Recovery Backup' or 'Apps/Drivers Recovery Backup'.
Make sure you keep the USB flash drive in a safe place that you
will remember.
5