Hello all,
I have had a wipout of 3 Kingston DataTraveller 16 GB and one Duracell 32 GB USB flash memory sticks. Not only is the data lost, they can't even be reformatted! (The data loss is no calamity - it was a duplicate backup.)
The one misbehaviour I had thoughtlessly done: For about 9 months long, these sticks were stored in an above-counter kitchen cabinet, on the bottom level, and that cabinet has an under-the-cabinet 24-inch fluorescent fixture (tube and ballast) for illuminating the countertop. I switched it on and off a few times a day. The USB sticks were stored about 8 inches / 20 cm away from one end of the fluorescent fixture, i.e., not quite directly above the fixture (otherwise the separation would only have been 1 inch / 2.5 cm).
So, does anyone know whether USB flash memory sticks (and presumably flash memory camera cards too) are particularly sensitive to electro-magnetic or other disturbances?
And what about smartphones? My smartphone was in a similar position for about 6 months, but is still working perfectly. (It's not there anymore!)
Hartmut W Sager - Tel +1-204-339-8331, +1-204-515-1701
On 2015-02-18 Hartmut W Sager wrote:
Hello all,
I have had a wipout of 3 Kingston DataTraveller 16 GB and one Duracell 32 GB USB flash memory sticks. Not only is the data lost, they can't even be reformatted! (The data loss is no calamity - it was a duplicate backup.)
This will sound weird, but the sticks may be / have been / still are good. Make sure you test the sticks (and the reformat) with a 2nd machine / 2nd card reader / 2nd usb cable / 2nd usb hub and/or all of the above. Make sure the contacts on the card and the reader are clean.
I recently had a new high-end sd card act weird and it was because of a usb1 cable (accident) to a unpowered gimmick usb hub chained 2 hubs deep that was corrupting signal intermittently, to a card reader with a flaky usb jack. The card behaved normally once I eliminated those problems.
Now I first mount all camera sd cards -o ro and do a cp (NOT mv!!) first, *then* remount rw and clean it out. Wacky stuff during a mv can permanently mess up your card data and result in lost pix. Wacky stuff during a -o ro cp shouldn't result in anything more than a chance to retry later.
The one misbehaviour I had thoughtlessly done: For about 9 months long, these sticks were stored in an above-counter kitchen cabinet, on the bottom level, and that cabinet has an under-the-cabinet 24-inch fluorescent fixture (tube and ballast) for illuminating the countertop. I switched it on and off a few times a day. The USB
Hmm, I haven't heard of that. I do believe they are not magnetic, and that a magnetic field could not change the trapped electrons, but I could be wrong.
The reason I suspect something like in my scenario is because it would be very strange that *all* those cards would go bad at once. There would be slight differences in location, etc, that would cause variation in your scenario.
You could test the theory by trying in your (unchanged) setup a known-good card that was not in that location.
Report back to us when you figure it out...
On 2015-02-18 Hartmut W Sager wrote:
Hello all,
Duracell 32 GB USB flash memory sticks. Not only is the data lost,
Oh, my brain didn't register you said "usb sticks", so ignore my bit about card readers as obviously that doesn't apply.
But the rest should hold. Try a different setup (every single part of the chain), even if it seems innocuous. Even a new system. Especially the reformatting part.
Is there a chance the sticks were exposed in the kitchen to too-high a heat/humidity, or dirt/food, etc? Perhaps its a contact issue. Or perhaps you have a bad (shorted) usb port you plugged them all into? Does a mouse work in the port you used (warning, may kill the mouse too)?
Lastly, I've had sticks act weird, like mega-slow (we're talking 1200 baud slow) but otherwise ok, then magically one day a year later when I'm about to chuck it out it works full speed (perhaps they are self-aware and know they are about to be chucked?).
Moral of the story is (cheap, but sometimes expensive) flash memory stinks (except in a supersmart bad-thing-compensating ssd) and should be trusted as little as possible.
-
Hartmut W Sager -
Trevor Cordes