USB/ webcam driver problem

Recently, I had to restore windows XP. Since then,
everything has been fine (much less blue screen errors,
hangups). I only had to manually search for drivers for
peripherals upon first time use (i.e. printer, scanner,
digital camera, portable mp3 player, etc...), usually in
I386, or Windows/system32. However, I am having a hard
time loading drivers for my 3com Homeconnect USB webcam,
and the USB portion of my Panasonic Palmcorder PV-DV702.
For the panasonic, when the computer boots up, I see the
notice that says Found New Hardware- USB Device, then I
get "Cannot Install This Hardware. The hardware was not
installed because the wizard cannot find the necessary
software.", even though I have the manufacturer's CD. I
also tried dl'ing the driver from the website, but even
though I run the setup.exe to install the driver, it's
still not installed after I reboot the computer. When I
use the firewire with the Panasonic it works fine, but
there are certain tasks I need to use with USB (webcam).

For the 3com, I'm supposed to be using the Vicam driver
from the website b/c the original drivers don't work with
XP, but like the Panasonic, after I run the exe to
install the driver, it's not installed after reboot.
Please tell me there's an easy solution for this problem.

The problem is not the USB port either, because I've
tried different ports and other peripherals have worked
with these same ports.



I've manually searched folders I386, windows/system32;
installed drivers from manufacturer's cd; installed
drivers downloaded from website; uninstalled/ reinstalled
all driver software; tried different USB ports.