Canon A800 - Manual (Page 93)

93
You can erase all images at once. Since erased images cannot be recovered,
exercise adequate caution before erasing. Protected images
(p. 92) cannot
be erased.
Choose [Erase all].
z Press the n button to choose [Erase
all] from the 1 tab, then press the m
button.
Erase all images.
z Press the qr buttons to choose [OK], then
press the m button.
Erasing All Images