If more than one camera used to work and now do not, and you have not reloaded XP and forgot to load motherboard drivers, then two suggestions. Make sure the port has not been disabled, and try a new cable.
I have a Cannon digital camcorder which used to be recognized by my Sony VAIO laptop, when hooked up to the firewire port. Now it does n't recognize the same and hence cannot upload any video clips to the PC. Neither does the PC recognize any other camcorders, which it used to do earlier. The op system is Windows XP, the preloaded version that came along with the PC. The PC has a built in fire wire port and not one which I have added.
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