Quote:
Originally Posted by DaleDe
Yea, I know all of that stuff but I still managed to corrupt a card. As I said I probably wasn't as careful as I should have been. However, it was only a card, not the firmware of the device. I recovered it by reformatting the card and reloading the eBooks.
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One tool I recommend for everyone who uses cards is a USB card reader.
Expansion cards are formatted with the MS-DOS FAT filesystem, and are subject to the same sort of errors that can corrupt FAT formatted disks. In particular, they can develop "lost clusters". The cluster is the smallest physical area of the disk readable and writable in one operation. (The size of a cluster varies depending on the size of the FAT formatted drive.) In a FAT file system, each cluster has a unique address. The File Allocation Table maintained by the OS maps what clusters are used by what files. It's possible for clusters to be marked as allocated in the FAT table, but not actually owned by any files. These are known as "lost" clusters, and they mightily confuse the OS and your programs.
The Windows Scandisk (Win 9X) and CHKDSK (WinNT/2K/XP/Vista) utilities can be used to check the status of disks and repair errors. Lost clusters are allocated to files with names like FILE0000.CHK, which can be examined and (likely) deleted. Once the lost clusters are cleaned up, the drive is often usable again.
Expansion cards can develop lost clusters, if a program writing to the card crashes, or the OS crashes. The FAT table isn't properly updated, and errors result. With a USB card reader, teh card is seen by Windows as a removable media drive by windows, and you can use Scandisk or CHKDSK from a command line in a DOS box, or right-click on on the drive in My Computer, select Properties, click the Tools tab, and click Check Now. Check the "Automatically fix file system errors" box.
If disk checking finds and fixes lost clusters, you'll see a directory on the card called FOUND.000, with FILEXXXX.CHK files in it that contain the contents of the located clusters CHKDSK located. (I usually just delete the folder. There is seldom anything worth preserving in it.)
I've had to do this on occasion with cards, and it made the cards usable without having to reformat and lose the contents.
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Dennis