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I'm in the market for a USB flash drive, and remember this cool feature a tiny 32MB flash drive of mine had: a write lock switch. This seemed like it would be an amazing feature to have as a shield against any nastiness happening to the drive on an unfamiliar computer. However, very few drives on the market offer this feature. Instead, it seems that forms of software protection are the more prominent method.

This software protection causes me a bit of uneasiness, as it seems like this software wouldn't be nearly as bulletproof as a physical switch. Also, levels of protection seem to vary from product to product. Being able to protect certain folders from reading and/or writing would be nice, but is the security trade-off worth it? Just how effective can this software protection be? Wouldn't a simple format be able to clean any drive with software protection?

My drive must also be compatible with Windows XP, Vista, and 7, as well as Linux and Mac.

What would be the best way forward for getting a well-sized (~8GB) flash drive with a strong write protection implementation, for little or no more than a regular drive?


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USB drive with a physical switch is the best solution. – Moab Jun 27 '11 at 0:46
If you mean software as in this method, I would think it should be bulletproof enough for most purposes. I don’t know for sure, but I would imagine that it is handled by low-level drivers, thus bypassing any user-mode level apps. Of course a virus would likely hook ring 0 and so a hardware switch would indeed be better. – Synetech Oct 26 '11 at 20:29
I got a 128MB flash drive for free for signing up for a web-seminar once, and it has a write-protect switch while none of the bigger ones I bought from the store have it. I guess they just figured (incorrectly) that it was not useful so they stopped including them later. :( – Bobson Mar 11 '12 at 20:21
up vote 3 down vote accepted

Memory cards pretty much always have a physical write-protect switch. You could use one of those on systems that have a card reader (apparently more and more common these days). You could also keep the card in a small USB card reader and use it as a unit, like a flash drive (there are some very small card-readers that are about are the same size as a flash drive) (1). Alternately, you could get a memory card that has a USB interface built-in (2), (3), or even hack one yourself (4).


Small, USB SD card-reader


SD card with built-in USB interface.


SD card with built-in USB interface


Hacked SD card, exposing USB interface

share|improve this answer
Good answer. That's what I'd do, too. +1 – Tyler Faile Jun 27 '11 at 2:20
David Pogue folds an SD card in a video about usability. – Bobson Mar 11 '12 at 20:24

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