What Happens to Lost Data
Deleted data from flash media cards is not really lost, but simply ignored by the
operating system. If you delete a file, the first letter of a directory entry is replaced
with a special character. In addition, information about the order of the clusters is
removed.
If the directory entries or the FAT or both are
incorrect or deleted, the operating system cannot
read anything. This is the reason why end-users
think data is gone. The data is still in the data
area, however. Finding this data can be difficult
because the entire drive must be examined.
If the file was not fragmented (that is, every clus-
ter for the file was stored successively), this loss
of sector information doesn’t really matter. If the
file was fragmented by frequent writing and
erasing, the chances for recovery are relatively
slim. Fortunately, file fragmentation on a flash
media card rarely occurs unless you have been using a card for months and selec-
tively remove images while retaining others.
If missing files are visible under the Deleted folder in PC Inspector File Recovery, you
can try to recover them, but you might be out of luck. File Recovery will assume the
files are not fragmented and try to recover them based on the maximum file size set
in Object, Options, Files. The end result is the recovery file might contain a lot of
garbage, especially if the drive was fragmented (the file’s information was spread all
over the disk).
Data is completely lost whenever content is damaged or overwritten. In this situa-
tion, the file was not lost because of incorrect information in the FAT or the directory
entries, but rather from one of the following causes:
■ The flash media is physically damaged.
■ Viruses or something else have destroyed the data.
■ Files have overwritten the disk.If files are to blame, only a portion of the image is recoverable. Believe it or not, half
an image can be recovered!106 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY
tip
If you’re up to it, defrag-
ment your flash media. Read
the section “Preventative
Maintenance: Defragmenting
Flash Media” in this chapter
for tips.