So, having managed to mangle my printer, which had a muticard reader built into it, I came to a point where I needed to connect the “big” camera up to the relatively new laptop.. but it just wasn’t happening. The diver simply wouldn’t install no matter what I tried, including grabbing various versions from both the canon site, and other driver distributors, and the sd card is now an almost obsolete size and thus isn’t supported on either my new laptop or desktop. It turns out that, in order to get Windows 7 to recognise the 350d as a camera at all, you have to go through the camera settings via the menu, and change the connection type and communication parameter from PC to print/PTP
Why? Well.. I have no idea, but… it works! I have no idea if the same thing is an issue with other Canon cameras but, I have to assume that others will have had the same issue and thus.. I’ve added the solution here for all to find and make use of.