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weshouldbegood
Jun 5, 2006, 04:43 PM
Hi. I'm just wondering if flash media (like Secure Digital cards) are erased or if there is any data corruption when a magnet is placed on the media. Thanks for letting me know!

-WeS

cajalat
Jun 5, 2006, 05:58 PM
Absolutely not. This is a pure myth. Go get the biggest magnet around and put some junk data on a flash card and see if you can erase anything on it with that magnet. You won't be able to. To understand why that is to take a look at how flash media is constructed and most importantly what it is constructed of and how it actually stores data. You see, Flash Media such as SD is non-magnetic.

So don't worry about magnets and your Flash Media.

weshouldbegood
Jun 5, 2006, 06:41 PM
Absolutely not. This is a pure myth. Go get the biggest magnet around and put some junk data on a flash card and see if you can erase anything on it with that magnet. You won't be able to. To understand why that is to take a look at how flash media is constructed and most importantly what it is constructed of and how it actually stores data. You see, Flash Media such as SD is non-magnetic.


Another question of mine is whether secure deletion software is still needed on Flash media when sensitive data is stored on the media. That is to say, when I delete files on a flash card is the whole file gone or just the file pointer.

Thanks!

cajalat
Jun 9, 2006, 04:02 AM
Deleting files only removes the pointer. You still need to use a technique to securely delete all data on flash. Proof is that there are plenty of commercial applications that allow you to recover deleted files off your flash.