Can't download from Canon A630 to PC

I have a brand new Canon A630 digital camera. When I connect the usb cable to my PC it appears to find it initially but then after a couple of seconds a message pops up saying there was a problem during installation and my new hardware might not work properly.And of course it doesn't work.
In device manager there is a yellow asterisk against it in 'imaging devices' with the advice in 'properties' as follows;
"windows cannot load the device driver for this hardware because a previous instance of the device driver is still in memory. (Code 38)"
Uninstalling the device in device manager doesnt help i go through the same routine over and over.
Performing System Restore back to a time before i first connected the camera doesnt work I still get the same message
The troubleshooter in the manual offers no suggestions that work.
The camera works fine on my PC at work so its not the camera .

I'm Running windows XP SP2 on Mesh Titan PC Athlon X2 3800
Surely i shouldn't have to uninstall the Windows XP digital camera driver? Any advice gratefully received before I start doing rash/risky things to resolve this!

Thanks