This is not the fault of windows.. this is a security loophole because of the DMA (direct memory access) feature in the spec of firewire. So even a mac or a linux box can be cracked if you have physical access to the machine and that one has a firewire port
Crack a Mac with Firewire
For more info: *www.engadget.com/2008/03/04/windows-passwords-easily-bypassed-over-firewire/
physical access is the key here... if you get physical access to a pc there are plenty of ways that its security can be compromised
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