XP is unable to detect a video camera through IEEE394 port

Hi

I tried attaching a video camera through the firewire
port on my machine. It was detected initially but has
stopped working subsequently.

How can i get the system to detect. When it was detected
in the past a couple of times, on the popup screen for
the camera, i had set no-action with the check
box 'always no action'. How can i reverse the situation.

I was trying to use ulead software and that is giving an
error as 'no capture drivers' when i am trying to stream.

Thanks in advance
Sudipto