If for some reason the password had to be reset to the original, the below config file can be changed to allow re-using passwords
edit /etc/pam.d/system-password
vi /etc/pam.d/system-password
change remember=5 to remember=1 and reboot the appliance
Once the appliance boots up, set the password using
passwd root
EDIT: The above does not work with the newer versions of VIDM!