video camera not recognized

how should i proceed to investigate a problem with a video camera not being
recognized? i've spent hours reading web postings about a video camera not begin
recognized
by a computer; it is a hugely popular subject. but i've never seen my problem
posted. (i apologize for the length of this post, but analysis requires it -- i
think.)

the following comments apply to three computers running windows xp pro sp2 and
two video cameras connected to the computers by ieee1394 firewire cable. for
brevity, i'll give each device a label:

"v1" canon vixia hv30 video camera
"v2" canon elura 100 video camera
"c1" dell dimension 8400 (four years old, or is it five)
"c2" dell xps ??? (three years old)
"c3" dell e1705 laptop (three years old)

c2 has had no windows update since c2 was installed. c1 and c3 have had all
updates microsoft cares to install, except sp3. and half a dozen recent security
updates have not been installed on c3.

tapes from v1 and v2 are copied to one of these computers and edited with adobe
premiere pro cs4, which i'll call "pp4."

here's how a properly functioning computer reacts when a firewire-attached video
camera is switched on in play mode:

above the system tray a balloon displays the camera name. that is followed by a
note that "avc device" is recognized. next, the "digital video device" dialog box
opens to provide a choice of what to do with the newly connected camera, such as
edit in pp4.

this correct behavior is seen when either v1 or v2 is connected to c2. this
behavior also occurs when v2 is switched on while connected to any of the three
comptuters. the v1 to c1 connection has worked recently, once. it now
consistently fails.

when v1 is attached to c1 or c3, no "digital video device" dialog box appears
and pp4 cannot control the camera. however, the computer audio gongs twice,
device manager refeshes its display twice and it adds to the device tree, in
"sound, video and game controllers, an entry for "av/c tape device." c3 shows
the name of the camera in a balloon above the system tray; c1 does not. when v1
is attached to c2 the "digital video device" dialog box promptly appears and pp4
can control v1.

how do i get the v1 connection to c1 and c3 to work?
--david