Strange modifications to HD

I wouldn't be posting this if it had just happened to my system, but it has now happened to 2 systems on our network, all fully patched and squeaky-clean. I was running my laptop at lunch today, and I shut down and moved to the room I was due in. When I started up, my computer was SOL. My C drive is now flagged as E, non-dos (OS/2) and not bootable. The same thing happened to the other system. There were absolutely no signs in either instance. In fact, I had just verified that everything was copasetic with my hard drive last night. Just wondering if this has happened to anyone else, or if you have any idea what could be causing it, apart from human error ? which I doubt is the cause. Thanks,

Binaryloc
nathan.fulton at gmail dot com

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